215990540 has 24 divisors (see below), whose sum is σ = 458680320. Its totient is φ = 85424768.

The previous prime is 215990531. The next prime is 215990543. The reversal of 215990540 is 45099512.

215990540 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 215990540.

It is not an unprimeable number, because it can be changed into a prime (215990543) 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, 58892 + ... + 62451.

It is an arithmetic number, because the mean of its divisors is an integer number (19111680).

Almost surely, 2^215990540 is an apocalyptic number.

215990540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215990540 is an abundant number, since it is smaller than the sum of its proper divisors (242689780).

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

215990540 is a wasteful number, since it uses less digits than its factorization.

215990540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121441 (or 121439 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 215990540 is about 14696.6166174395. The cubic root of 215990540 is about 599.9912406129.

The spelling of 215990540 in words is "two hundred fifteen million, nine hundred ninety thousand, five hundred forty".