215204451012561 has 16 divisors (see below), whose sum is σ = 296221297301504. Its totient is φ = 138868801311744.

The previous prime is 215204451012559. The next prime is 215204451012599. The reversal of 215204451012561 is 165210154402512.

It is not a de Polignac number, because 215204451012561 - 2¹ = 215204451012559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215204451016561) 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, 5022721681 + ... + 5022764526.

It is an arithmetic number, because the mean of its divisors is an integer number (18513831081344).

Almost surely, 2^{215204451012561} is an apocalyptic number.

It is an amenable number.

215204451012561 is a deficient number, since it is larger than the sum of its proper divisors (81016846288943).

215204451012561 is a wasteful number, since it uses less digits than its factorization.

215204451012561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10045486440.

The product of its (nonzero) digits is 96000, while the sum is 39.

The spelling of 215204451012561 in words is "two hundred fifteen trillion, two hundred four billion, four hundred fifty-one million, twelve thousand, five hundred sixty-one".