18720972 has 36 divisors (see below), whose sum is σ = 47862360. Its totient is φ = 6169152.

The previous prime is 18720967. The next prime is 18721007. The reversal of 18720972 is 27902781.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 283 + ... + 6125.

It is an arithmetic number, because the mean of its divisors is an integer number (1329510).

Almost surely, 2^18720972 is an apocalyptic number.

18720972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18720972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23931180).

18720972 is an abundant number, since it is smaller than the sum of its proper divisors (29141388).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18720972 is a wasteful number, since it uses less digits than its factorization.

18720972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5942 (or 5937 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 18720972 is about 4326.7738558885. The cubic root of 18720972 is about 265.5274743611.

The spelling of 18720972 in words is "eighteen million, seven hundred twenty thousand, nine hundred seventy-two".