1239451897 has 2 divisors, whose sum is σ = 1239451898. Its totient is φ = 1239451896.

The previous prime is 1239451883. The next prime is 1239451903. The reversal of 1239451897 is 7981549321.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1041740176 + 197711721 = 32276^2 + 14061^2 .

It is an emirp because it is prime and its reverse (7981549321) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1239451897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1239451897.

It is not a weakly prime, because it can be changed into another prime (1239451817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 619725948 + 619725949.

It is an arithmetic number, because the mean of its divisors is an integer number (619725949).

Almost surely, 2^1239451897 is an apocalyptic number.

It is an amenable number.

1239451897 is a deficient number, since it is larger than the sum of its proper divisors (1).

1239451897 is an equidigital number, since it uses as much as digits as its factorization.

1239451897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 49.

The square root of 1239451897 is about 35205.8503234903. The cubic root of 1239451897 is about 1074.1787553563.

The spelling of 1239451897 in words is "one billion, two hundred thirty-nine million, four hundred fifty-one thousand, eight hundred ninety-seven".