16947981 has 16 divisors (see below), whose sum is σ = 26430400. Its totient is φ = 10703664.

The previous prime is 16947971. The next prime is 16948007. The reversal of 16947981 is 18974961.

It is a happy number.

It is not a de Polignac number, because 16947981 - 2¹⁴ = 16931597 is a prime.

It is a super-2 number, since 2×16947981² = 574468119952722, 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 (16947911) 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, 16006 + ... + 17031.

It is an arithmetic number, because the mean of its divisors is an integer number (1651900).

Almost surely, 2^16947981 is an apocalyptic number.

It is an amenable number.

16947981 is a deficient number, since it is larger than the sum of its proper divisors (9482419).

16947981 is a wasteful number, since it uses less digits than its factorization.

16947981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33065 (or 33059 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 16947981 is about 4116.7925621775. The cubic root of 16947981 is about 256.8656254238.

The spelling of 16947981 in words is "sixteen million, nine hundred forty-seven thousand, nine hundred eighty-one".