1213013231 has 4 divisors (see below), whose sum is σ = 1213827192. Its totient is φ = 1212199272.

The previous prime is 1213013209. The next prime is 1213013239. The reversal of 1213013231 is 1323103121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1213013231 - 2²² = 1208818927 is a prime.

It is a super-2 number, since 2×1213013231² = 2942802197162118722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213013239) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 404741 + ... + 407726.

It is an arithmetic number, because the mean of its divisors is an integer number (303456798).

Almost surely, 2^1213013231 is an apocalyptic number.

1213013231 is a deficient number, since it is larger than the sum of its proper divisors (813961).

1213013231 is an equidigital number, since it uses as much as digits as its factorization.

1213013231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 813960.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 1213013231 is about 34828.3394809457. The cubic root of 1213013231 is about 1066.4860505491.

Adding to 1213013231 its reverse (1323103121), we get a palindrome (2536116352).

The spelling of 1213013231 in words is "one billion, two hundred thirteen million, thirteen thousand, two hundred thirty-one".