1252698721 has 2 divisors, whose sum is σ = 1252698722. Its totient is φ = 1252698720.

The previous prime is 1252698683. The next prime is 1252698739. The reversal of 1252698721 is 1278962521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 832899600 + 419799121 = 28860^2 + 20489^2 .

It is a cyclic number.

It is not a de Polignac number, because 1252698721 - 2¹³ = 1252690529 is a prime.

It is not a weakly prime, because it can be changed into another prime (1252698781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 626349360 + 626349361.

It is an arithmetic number, because the mean of its divisors is an integer number (626349361).

Almost surely, 2^1252698721 is an apocalyptic number.

It is an amenable number.

1252698721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1252698721 is an equidigital number, since it uses as much as digits as its factorization.

1252698721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 43.

The square root of 1252698721 is about 35393.4841602236. The cubic root of 1252698721 is about 1077.9920168691.

The spelling of 1252698721 in words is "one billion, two hundred fifty-two million, six hundred ninety-eight thousand, seven hundred twenty-one".