1209890231 has 8 divisors (see below), whose sum is σ = 1320138000. Its totient is φ = 1099685440.

The previous prime is 1209890219. The next prime is 1209890243. The reversal of 1209890231 is 1320989021.

It is an interprime number because it is at equal distance from previous prime (1209890219) and next prime (1209890243).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1209890231 - 2¹⁰ = 1209889207 is a prime.

It is a super-2 number, since 2×1209890231² = 2927668742138466722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1209890191 and 1209890200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1209895231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86195 + ... + 99243.

It is an arithmetic number, because the mean of its divisors is an integer number (165017250).

Almost surely, 2^1209890231 is an apocalyptic number.

1209890231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1209890231 is a deficient number, since it is larger than the sum of its proper divisors (110247769).

1209890231 is a wasteful number, since it uses less digits than its factorization.

1209890231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21489.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 1209890231 is about 34783.4764076278. The cubic root of 1209890231 is about 1065.5700126263.

It can be divided in two parts, 1209890 and 231, that added together give a palindrome (1210121).

The spelling of 1209890231 in words is "one billion, two hundred nine million, eight hundred ninety thousand, two hundred thirty-one".