2156512103621 has 2 divisors, whose sum is σ = 2156512103622. Its totient is φ = 2156512103620.

The previous prime is 2156512103611. The next prime is 2156512103623. The reversal of 2156512103621 is 1263012156512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1554784548100 + 601727555521 = 1246910^2 + 775711^2 .

It is a cyclic number.

It is not a de Polignac number, because 2156512103621 - 2²² = 2156507909317 is a prime.

Together with 2156512103623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2156512103623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078256051810 + 1078256051811.

It is an arithmetic number, because the mean of its divisors is an integer number (1078256051811).

Almost surely, 2^{2156512103621} is an apocalyptic number.

It is an amenable number.

2156512103621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156512103621 is an equidigital number, since it uses as much as digits as its factorization.

2156512103621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 35.

The spelling of 2156512103621 in words is "two trillion, one hundred fifty-six billion, five hundred twelve million, one hundred three thousand, six hundred twenty-one".