16400664 has 64 divisors (see below), whose sum is σ = 52070400. Its totient is φ = 4685472.

The previous prime is 16400647. The next prime is 16400669. The reversal of 16400664 is 46600461.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16400669) 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, 3912 + ... + 6935.

It is an arithmetic number, because the mean of its divisors is an integer number (813600).

Almost surely, 2^16400664 is an apocalyptic number.

16400664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

16400664 is an abundant number, since it is smaller than the sum of its proper divisors (35669736).

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

16400664 is a wasteful number, since it uses less digits than its factorization.

16400664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10869 (or 10859 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 16400664 is about 4049.7733269900. The cubic root of 16400664 is about 254.0702473775.

The spelling of 16400664 in words is "sixteen million, four hundred thousand, six hundred sixty-four".