19138561972 has 12 divisors (see below), whose sum is σ = 33896007936. Its totient is φ = 9453988280.

The previous prime is 19138561969. The next prime is 19138561973. The reversal of 19138561972 is 27916583191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19138561973) 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, 28822804 + ... + 28823467.

It is an arithmetic number, because the mean of its divisors is an integer number (2824667328).

Almost surely, 2^19138561972 is an apocalyptic number.

It is an amenable number.

19138561972 is a deficient number, since it is larger than the sum of its proper divisors (14757445964).

19138561972 is a wasteful number, since it uses less digits than its factorization.

19138561972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57646358 (or 57646356 counting only the distinct ones).

The product of its digits is 816480, while the sum is 52.

The spelling of 19138561972 in words is "nineteen billion, one hundred thirty-eight million, five hundred sixty-one thousand, nine hundred seventy-two".