1215525131 has 2 divisors, whose sum is σ = 1215525132. Its totient is φ = 1215525130.

The previous prime is 1215525127. The next prime is 1215525173. The reversal of 1215525131 is 1315255121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1215525131 - 2² = 1215525127 is a prime.

It is a super-2 number, since 2×1215525131² = 2955002688185134322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1215525131.

It is not a weakly prime, because it can be changed into another prime (1215525121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607762565 + 607762566.

It is an arithmetic number, because the mean of its divisors is an integer number (607762566).

Almost surely, 2^1215525131 is an apocalyptic number.

1215525131 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215525131 is an equidigital number, since it uses as much as digits as its factorization.

1215525131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1500, while the sum is 26.

The square root of 1215525131 is about 34864.3819821892. The cubic root of 1215525131 is about 1067.2217004751.

The spelling of 1215525131 in words is "one billion, two hundred fifteen million, five hundred twenty-five thousand, one hundred thirty-one".