18739797 has 16 divisors (see below), whose sum is σ = 27173952. Its totient is φ = 11439360.

The previous prime is 18739789. The next prime is 18739801. The reversal of 18739797 is 79793781.

It is a happy number.

It is not a de Polignac number, because 18739797 - 2³ = 18739789 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18739727) 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, 3079 + ... + 6852.

It is an arithmetic number, because the mean of its divisors is an integer number (1698372).

Almost surely, 2^18739797 is an apocalyptic number.

18739797 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18739797 is a deficient number, since it is larger than the sum of its proper divisors (8434155).

18739797 is a wasteful number, since it uses less digits than its factorization.

18739797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9988.

The product of its digits is 666792, while the sum is 51.

The square root of 18739797 is about 4328.9487176450. The cubic root of 18739797 is about 265.6164455284.

The spelling of 18739797 in words is "eighteen million, seven hundred thirty-nine thousand, seven hundred ninety-seven".