1372197809 has 2 divisors, whose sum is σ = 1372197810. Its totient is φ = 1372197808.

The previous prime is 1372197781. The next prime is 1372197821. The reversal of 1372197809 is 9087912731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1014231409 + 357966400 = 31847^2 + 18920^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1372197809 is a prime.

It is not a weakly prime, because it can be changed into another prime (1372197829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 686098904 + 686098905.

It is an arithmetic number, because the mean of its divisors is an integer number (686098905).

Almost surely, 2^1372197809 is an apocalyptic number.

It is an amenable number.

1372197809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1372197809 is an equidigital number, since it uses as much as digits as its factorization.

1372197809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 190512, while the sum is 47.

The square root of 1372197809 is about 37043.1884291836. The cubic root of 1372197809 is about 1111.2341355487.

The spelling of 1372197809 in words is "one billion, three hundred seventy-two million, one hundred ninety-seven thousand, eight hundred nine".