19597979 has 4 divisors (see below), whose sum is σ = 19718376. Its totient is φ = 19477584.

The previous prime is 19597961. The next prime is 19597999. The reversal of 19597979 is 97979591.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97979591 = 83 ⋅1180477.

It is a cyclic number.

It is not a de Polignac number, because 19597979 - 2²⁰ = 18549403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19597999) 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, 59954 + ... + 60279.

It is an arithmetic number, because the mean of its divisors is an integer number (4929594).

Almost surely, 2^19597979 is an apocalyptic number.

19597979 is a deficient number, since it is larger than the sum of its proper divisors (120397).

19597979 is a wasteful number, since it uses less digits than its factorization.

19597979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120396.

The product of its digits is 1607445, while the sum is 56.

The square root of 19597979 is about 4426.9604696676. The cubic root of 19597979 is about 269.6106826196.

The spelling of 19597979 in words is "nineteen million, five hundred ninety-seven thousand, nine hundred seventy-nine".