215540017056 has 576 divisors, whose sum is σ = 819769466880. Its totient is φ = 52112885760.

The previous prime is 215540017039. The next prime is 215540017073. The reversal of 215540017056 is 650710045512.

It is an interprime number because it is at equal distance from previous prime (215540017039) and next prime (215540017073).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 215540017056.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 15429531 + ... + 15443493.

It is an arithmetic number, because the mean of its divisors is an integer number (1423210880).

Almost surely, 2^215540017056 is an apocalyptic number.

215540017056 is a gapful number since it is divisible by the number (26) 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 215540017056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409884733440).

215540017056 is an abundant number, since it is smaller than the sum of its proper divisors (604229449824).

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

215540017056 is a wasteful number, since it uses less digits than its factorization.

215540017056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14049 (or 14038 counting only the distinct ones).

The product of its (nonzero) digits is 42000, while the sum is 36.

The spelling of 215540017056 in words is "two hundred fifteen billion, five hundred forty million, seventeen thousand, fifty-six".