15981404 has 6 divisors (see below), whose sum is σ = 27967464. Its totient is φ = 7990700.

The previous prime is 15981397. The next prime is 15981419. The reversal of 15981404 is 40418951.

It is a super-2 number, since 2×15981404² = 510810547622432, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1997672 + ... + 1997679.

It is an arithmetic number, because the mean of its divisors is an integer number (4661244).

Almost surely, 2^15981404 is an apocalyptic number.

It is an amenable number.

15981404 is a deficient number, since it is larger than the sum of its proper divisors (11986060).

15981404 is a wasteful number, since it uses less digits than its factorization.

15981404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3995355 (or 3995353 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 15981404 is about 3997.6748241947. The cubic root of 15981404 is about 251.8865492511.

The spelling of 15981404 in words is "fifteen million, nine hundred eighty-one thousand, four hundred four".