19977028 has 6 divisors (see below), whose sum is σ = 34959806. Its totient is φ = 9988512.

The previous prime is 19977019. The next prime is 19977043. The reversal of 19977028 is 82077991.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17994564 + 1982464 = 4242^2 + 1408^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2497125 + ... + 2497132.

Almost surely, 2^19977028 is an apocalyptic number.

It is an amenable number.

19977028 is a deficient number, since it is larger than the sum of its proper divisors (14982778).

19977028 is a wasteful number, since it uses less digits than its factorization.

19977028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4994261 (or 4994259 counting only the distinct ones).

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 19977028 is about 4469.5668693957. The cubic root of 19977028 is about 271.3377958418.

It can be divided in two parts, 1997 and 7028, that added together give a square (9025 = 95²).

The spelling of 19977028 in words is "nineteen million, nine hundred seventy-seven thousand, twenty-eight".