2156206526521 has 16 divisors (see below), whose sum is σ = 2192991252480. Its totient is φ = 2119560909840.

The previous prime is 2156206526501. The next prime is 2156206526531. The reversal of 2156206526521 is 1256256026512.

It is a cyclic number.

It is not a de Polignac number, because 2156206526521 - 2¹³ = 2156206518329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2156206526501) 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, 83694040 + ... + 83719798.

It is an arithmetic number, because the mean of its divisors is an integer number (137061953280).

Almost surely, 2^{2156206526521} is an apocalyptic number.

It is an amenable number.

2156206526521 is a deficient number, since it is larger than the sum of its proper divisors (36784725959).

2156206526521 is a wasteful number, since it uses less digits than its factorization.

2156206526521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28404.

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 2156206526521 in words is "two trillion, one hundred fifty-six billion, two hundred six million, five hundred twenty-six thousand, five hundred twenty-one".