15625257211381 has 2 divisors, whose sum is σ = 15625257211382. Its totient is φ = 15625257211380.

The previous prime is 15625257211339. The next prime is 15625257211433. The reversal of 15625257211381 is 18311275252651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8382565210756 + 7242692000625 = 2895266^2 + 2691225^2 .

It is a cyclic number.

It is not a de Polignac number, because 15625257211381 - 2⁹ = 15625257210869 is a prime.

It is a super-2 number, since 2×15625257211381² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15625257211181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7812628605690 + 7812628605691.

It is an arithmetic number, because the mean of its divisors is an integer number (7812628605691).

Almost surely, 2^{15625257211381} is an apocalyptic number.

It is an amenable number.

15625257211381 is a deficient number, since it is larger than the sum of its proper divisors (1).

15625257211381 is an equidigital number, since it uses as much as digits as its factorization.

15625257211381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008000, while the sum is 49.

The spelling of 15625257211381 in words is "fifteen trillion, six hundred twenty-five billion, two hundred fifty-seven million, two hundred eleven thousand, three hundred eighty-one".