19777972 has 12 divisors (see below), whose sum is σ = 34761636. Its totient is φ = 9846080.

The previous prime is 19777951. The next prime is 19777991. The reversal of 19777972 is 27977791.

It can be written as a sum of positive squares in 2 ways, for example, as 12574116 + 7203856 = 3546^2 + 2684^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9679 + ... + 11542.

It is an arithmetic number, because the mean of its divisors is an integer number (2896803).

Almost surely, 2^19777972 is an apocalyptic number.

It is an amenable number.

19777972 is a deficient number, since it is larger than the sum of its proper divisors (14983664).

19777972 is a wasteful number, since it uses less digits than its factorization.

19777972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21458 (or 21456 counting only the distinct ones).

The product of its digits is 388962, while the sum is 49.

The square root of 19777972 is about 4447.2431910117. The cubic root of 19777972 is about 270.4335603981.

The spelling of 19777972 in words is "nineteen million, seven hundred seventy-seven thousand, nine hundred seventy-two".