2251206531421 has 16 divisors (see below), whose sum is σ = 2385907472448. Its totient is φ = 2116759622400.

The previous prime is 2251206531391. The next prime is 2251206531443. The reversal of 2251206531421 is 1241356021522.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2251206531421 - 2¹⁹ = 2251206007133 is a prime.

It is a super-2 number, since 2×2251206531421² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2251206531121) 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, 81043491 + ... + 81071263.

It is an arithmetic number, because the mean of its divisors is an integer number (149119217028).

Almost surely, 2^{2251206531421} is an apocalyptic number.

It is an amenable number.

2251206531421 is a deficient number, since it is larger than the sum of its proper divisors (134700941027).

2251206531421 is a wasteful number, since it uses less digits than its factorization.

2251206531421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32172.

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 2251206531421 in words is "two trillion, two hundred fifty-one billion, two hundred six million, five hundred thirty-one thousand, four hundred twenty-one".