1251428697 has 10 divisors (see below), whose sum is σ = 1869418298. Its totient is φ = 834285744.

The previous prime is 1251428687. The next prime is 1251428713. The reversal of 1251428697 is 7968241521.

It can be written as a sum of positive squares in only one way, i.e., 1079713881 + 171714816 = 32859^2 + 13104^2 .

It is not a de Polignac number, because 1251428697 - 2⁴ = 1251428681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1251428687) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 7724788 + ... + 7724949.

Almost surely, 2^1251428697 is an apocalyptic number.

It is an amenable number.

1251428697 is a deficient number, since it is larger than the sum of its proper divisors (617989601).

1251428697 is an equidigital number, since it uses as much as digits as its factorization.

1251428697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15449749 (or 15449740 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 1251428697 is about 35375.5381160485. The cubic root of 1251428697 is about 1077.6275933406.

The spelling of 1251428697 in words is "one billion, two hundred fifty-one million, four hundred twenty-eight thousand, six hundred ninety-seven".