128772251 has 2 divisors, whose sum is σ = 128772252. Its totient is φ = 128772250.

The previous prime is 128772221. The next prime is 128772271. The reversal of 128772251 is 152277821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128772251 - 2²⁶ = 61663387 is a prime.

It is not a weakly prime, because it can be changed into another prime (128772211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64386125 + 64386126.

It is an arithmetic number, because the mean of its divisors is an integer number (64386126).

Almost surely, 2^128772251 is an apocalyptic number.

128772251 is a deficient number, since it is larger than the sum of its proper divisors (1).

128772251 is an equidigital number, since it uses as much as digits as its factorization.

128772251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15680, while the sum is 35.

The square root of 128772251 is about 11347.7861717606. The cubic root of 128772251 is about 504.9799044384.

The spelling of 128772251 in words is "one hundred twenty-eight million, seven hundred seventy-two thousand, two hundred fifty-one".