16401690 has 40 divisors (see below), whose sum is σ = 44104500. Its totient is φ = 4373568.

The previous prime is 16401641. The next prime is 16401701. The reversal of 16401690 is 9610461.

16401690 is a `hidden beast` number, since 1 + 640 + 16 + 9 + 0 = 666.

16401690 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 15896169 + 505521 = 3987^2 + 711^2 .

It is a super-2 number, since 2×16401690² = 538030869712200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9315 + ... + 10934.

Almost surely, 2^16401690 is an apocalyptic number.

16401690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16401690 is an abundant number, since it is smaller than the sum of its proper divisors (27702810).

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

16401690 is a wasteful number, since it uses less digits than its factorization.

16401690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20268 (or 20259 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 16401690 is about 4049.8999987654. The cubic root of 16401690 is about 254.0755453467.

The spelling of 16401690 in words is "sixteen million, four hundred one thousand, six hundred ninety".