15870981 has 16 divisors (see below), whose sum is σ = 24288768. Its totient is φ = 9030000.

The previous prime is 15870971. The next prime is 15870983. The reversal of 15870981 is 18907851.

It is not a de Polignac number, because 15870981 - 2⁵ = 15870949 is a prime.

It is a super-2 number, since 2×15870981² = 503776075804722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15870983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3766 + ... + 6776.

It is an arithmetic number, because the mean of its divisors is an integer number (1518048).

Almost surely, 2^15870981 is an apocalyptic number.

It is an amenable number.

15870981 is a deficient number, since it is larger than the sum of its proper divisors (8417787).

15870981 is a wasteful number, since it uses less digits than its factorization.

15870981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3272.

The product of its (nonzero) digits is 20160, while the sum is 39.

The square root of 15870981 is about 3983.8399817262. The cubic root of 15870981 is about 251.3050739396.

The spelling of 15870981 in words is "fifteen million, eight hundred seventy thousand, nine hundred eighty-one".