1251797320 has 32 divisors (see below), whose sum is σ = 2892670200. Its totient is φ = 487185408.

The previous prime is 1251797303. The next prime is 1251797347. The reversal of 1251797320 is 237971521.

It can be written as a sum of positive squares in 4 ways, for example, as 905167396 + 346629924 = 30086^2 + 18618^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 1251797320.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 421425 + ... + 424384.

Almost surely, 2^1251797320 is an apocalyptic number.

1251797320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251797320 is an abundant number, since it is smaller than the sum of its proper divisors (1640872880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1251797320 is a wasteful number, since it uses less digits than its factorization.

1251797320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 845857 (or 845853 counting only the distinct ones).

The product of its (nonzero) digits is 26460, while the sum is 37.

The square root of 1251797320 is about 35380.7478722539. The cubic root of 1251797320 is about 1077.7333922353.

The spelling of 1251797320 in words is "one billion, two hundred fifty-one million, seven hundred ninety-seven thousand, three hundred twenty".