215012640 has 48 divisors (see below), whose sum is σ = 677291328. Its totient is φ = 57336576.

The previous prime is 215012597. The next prime is 215012659. The reversal of 215012640 is 46210512.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 223492 + ... + 224451.

It is an arithmetic number, because the mean of its divisors is an integer number (14110236).

Almost surely, 2^215012640 is an apocalyptic number.

215012640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215012640 is an abundant number, since it is smaller than the sum of its proper divisors (462278688).

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

215012640 is a wasteful number, since it uses less digits than its factorization.

215012640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447961 (or 447953 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 215012640 is about 14663.3093127029. The cubic root of 215012640 is about 599.0843812256.

The spelling of 215012640 in words is "two hundred fifteen million, twelve thousand, six hundred forty".