16971990 has 32 divisors (see below), whose sum is σ = 46552320. Its totient is φ = 3879264.

The previous prime is 16971979. The next prime is 16972009. The reversal of 16971990 is 9917961.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40200 + ... + 40619.

It is an arithmetic number, because the mean of its divisors is an integer number (1454760).

Almost surely, 2^16971990 is an apocalyptic number.

16971990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16971990 is an abundant number, since it is smaller than the sum of its proper divisors (29580330).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16971990 is a wasteful number, since it uses less digits than its factorization.

16971990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80836.

The product of its (nonzero) digits is 30618, while the sum is 42.

The square root of 16971990 is about 4119.7075138898. The cubic root of 16971990 is about 256.9868626168.

The spelling of 16971990 in words is "sixteen million, nine hundred seventy-one thousand, nine hundred ninety".