15664040 has 64 divisors (see below), whose sum is σ = 41247360. Its totient is φ = 5241600.

The previous prime is 15664039. The next prime is 15664043. The reversal of 15664040 is 4046651.

It is a happy number.

15664040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15664043) 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, 11390 + ... + 12690.

It is an arithmetic number, because the mean of its divisors is an integer number (644490).

Almost surely, 2^15664040 is an apocalyptic number.

15664040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15664040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20623680).

15664040 is an abundant number, since it is smaller than the sum of its proper divisors (25583320).

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

15664040 is a wasteful number, since it uses less digits than its factorization.

15664040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1362 (or 1358 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 15664040 is about 3957.7822072469. The cubic root of 15664040 is about 250.2080401625.

The spelling of 15664040 in words is "fifteen million, six hundred sixty-four thousand, forty".