125515553 has 2 divisors, whose sum is σ = 125515554. Its totient is φ = 125515552.

The previous prime is 125515519. The next prime is 125515561. The reversal of 125515553 is 355515521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110523169 + 14992384 = 10513^2 + 3872^2 .

It is a cyclic number.

It is not a de Polignac number, because 125515553 - 2¹⁴ = 125499169 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (125515513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62757776 + 62757777.

It is an arithmetic number, because the mean of its divisors is an integer number (62757777).

Almost surely, 2^125515553 is an apocalyptic number.

It is an amenable number.

125515553 is a deficient number, since it is larger than the sum of its proper divisors (1).

125515553 is an equidigital number, since it uses as much as digits as its factorization.

125515553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18750, while the sum is 32.

The square root of 125515553 is about 11203.3723940606. The cubic root of 125515553 is about 500.6864611110.

Subtracting from 125515553 its sum of digits (32), we obtain a palindrome (125515521).

The spelling of 125515553 in words is "one hundred twenty-five million, five hundred fifteen thousand, five hundred fifty-three".