1239393857 has 16 divisors (see below), whose sum is σ = 1458842112. Its totient is φ = 1042018560.

The previous prime is 1239393787. The next prime is 1239393877. The reversal of 1239393857 is 7583939321.

It is a cyclic number.

It is not a de Polignac number, because 1239393857 - 2¹² = 1239389761 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1239393877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83603 + ... + 97304.

It is an arithmetic number, because the mean of its divisors is an integer number (91177632).

Almost surely, 2^1239393857 is an apocalyptic number.

1239393857 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1239393857 is a deficient number, since it is larger than the sum of its proper divisors (219448255).

1239393857 is a wasteful number, since it uses less digits than its factorization.

1239393857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180968.

The product of its digits is 1224720, while the sum is 50.

The square root of 1239393857 is about 35205.0260190218. The cubic root of 1239393857 is about 1074.1619881847.

The spelling of 1239393857 in words is "one billion, two hundred thirty-nine million, three hundred ninety-three thousand, eight hundred fifty-seven".