15161981 has 8 divisors (see below), whose sum is σ = 16077600. Its totient is φ = 14258160.

The previous prime is 15161969. The next prime is 15161987. The reversal of 15161981 is 18916151.

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 15161981 - 2¹⁴ = 15145597 is a prime.

It is a super-2 number, since 2×15161981² = 459771335688722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15161987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 230 + ... + 5511.

It is an arithmetic number, because the mean of its divisors is an integer number (2009700).

Almost surely, 2^15161981 is an apocalyptic number.

It is an amenable number.

15161981 is a deficient number, since it is larger than the sum of its proper divisors (915619).

15161981 is a wasteful number, since it uses less digits than its factorization.

15161981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5899.

The product of its digits is 2160, while the sum is 32.

The square root of 15161981 is about 3893.8388513137. The cubic root of 15161981 is about 247.5057632233.

The spelling of 15161981 in words is "fifteen million, one hundred sixty-one thousand, nine hundred eighty-one".