19311872 has 18 divisors (see below), whose sum is σ = 38548818. Its totient is φ = 9655808.

The previous prime is 19311871. The next prime is 19311899. The reversal of 19311872 is 27811391.

It can be written as a sum of positive squares in only one way, i.e., 19219456 + 92416 = 4384^2 + 304^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19311871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37463 + ... + 37974.

It is an arithmetic number, because the mean of its divisors is an integer number (2141601).

Almost surely, 2^19311872 is an apocalyptic number.

It is an amenable number.

19311872 is a deficient number, since it is larger than the sum of its proper divisors (19236946).

19311872 is an frugal number, since it uses more digits than its factorization.

19311872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75453 (or 75439 counting only the distinct ones).

The product of its digits is 3024, while the sum is 32.

The square root of 19311872 is about 4394.5275058873. The cubic root of 19311872 is about 268.2922482095.

The spelling of 19311872 in words is "nineteen million, three hundred eleven thousand, eight hundred seventy-two".