1981825231 has 8 divisors (see below), whose sum is σ = 1995522480. Its totient is φ = 1968147072.

The previous prime is 1981825193. The next prime is 1981825253. The reversal of 1981825231 is 1325281891.

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 1981825231 - 2¹³ = 1981817039 is a prime.

It is a super-2 number, since 2×1981825231² = 7855262492456406722, 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 (1981825831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 249225 + ... + 257053.

It is an arithmetic number, because the mean of its divisors is an integer number (249440310).

Almost surely, 2^1981825231 is an apocalyptic number.

1981825231 is a deficient number, since it is larger than the sum of its proper divisors (13697249).

1981825231 is a wasteful number, since it uses less digits than its factorization.

1981825231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9545.

The product of its digits is 34560, while the sum is 40.

The square root of 1981825231 is about 44517.6957063144. The cubic root of 1981825231 is about 1256.0929682813.

The spelling of 1981825231 in words is "one billion, nine hundred eighty-one million, eight hundred twenty-five thousand, two hundred thirty-one".