2156553324261 has 32 divisors (see below), whose sum is σ = 3653022931200. Its totient is φ = 1231737131520.

The previous prime is 2156553324221. The next prime is 2156553324271. The reversal of 2156553324261 is 1624233556512.

2156553324261 is a `hidden beast` number, since 2 + 1 + 5 + 6 + 55 + 332 + 4 + 261 = 666.

It is not a de Polignac number, because 2156553324261 - 2⁶ = 2156553324197 is a prime.

It is a super-2 number, since 2×2156553324261² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2156553324221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2277360 + ... + 3082121.

It is an arithmetic number, because the mean of its divisors is an integer number (114156966600).

Almost surely, 2^{2156553324261} is an apocalyptic number.

2156553324261 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2156553324261 is a deficient number, since it is larger than the sum of its proper divisors (1496469606939).

2156553324261 is a wasteful number, since it uses less digits than its factorization.

2156553324261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5361626 (or 5361620 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 45.

The spelling of 2156553324261 in words is "two trillion, one hundred fifty-six billion, five hundred fifty-three million, three hundred twenty-four thousand, two hundred sixty-one".