215384664 has 32 divisors (see below), whose sum is σ = 587413440. Its totient is φ = 65268000.

The previous prime is 215384647. The next prime is 215384669. The reversal of 215384664 is 466483512.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215384669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 407662 + ... + 408189.

It is an arithmetic number, because the mean of its divisors is an integer number (18356670).

Almost surely, 2^215384664 is an apocalyptic number.

215384664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

215384664 is an abundant number, since it is smaller than the sum of its proper divisors (372028776).

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

215384664 is a wasteful number, since it uses less digits than its factorization.

215384664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815871 (or 815867 counting only the distinct ones).

The product of its digits is 138240, while the sum is 39.

The square root of 215384664 is about 14675.9893703968. The cubic root of 215384664 is about 599.4297025509.

The spelling of 215384664 in words is "two hundred fifteen million, three hundred eighty-four thousand, six hundred sixty-four".