1597994791 has 4 divisors (see below), whose sum is σ = 1682099800. Its totient is φ = 1513889784.

The previous prime is 1597994773. The next prime is 1597994809. The reversal of 1597994791 is 1974997951.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1597994773) and next prime (1597994809).

It is a cyclic number.

It is not a de Polignac number, because 1597994791 - 2⁷ = 1597994663 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1597994701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42052476 + ... + 42052513.

It is an arithmetic number, because the mean of its divisors is an integer number (420524950).

Almost surely, 2^1597994791 is an apocalyptic number.

1597994791 is a deficient number, since it is larger than the sum of its proper divisors (84105009).

1597994791 is an equidigital number, since it uses as much as digits as its factorization.

1597994791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84105008.

The product of its digits is 6429780, while the sum is 61.

The square root of 1597994791 is about 39974.9270293268. The cubic root of 1597994791 is about 1169.1182854700.

The spelling of 1597994791 in words is "one billion, five hundred ninety-seven million, nine hundred ninety-four thousand, seven hundred ninety-one".