18691372 has 12 divisors (see below), whose sum is σ = 37382800. Its totient is φ = 8010576.

The previous prime is 18691339. The next prime is 18691391. The reversal of 18691372 is 27319681.

18691372 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 333747 + ... + 333802.

Almost surely, 2^18691372 is an apocalyptic number.

It is an amenable number.

18691372 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18691372 is a wasteful number, since it uses less digits than its factorization.

18691372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667560 (or 667558 counting only the distinct ones).

The product of its digits is 18144, while the sum is 37.

The square root of 18691372 is about 4323.3519403352. The cubic root of 18691372 is about 265.3874574289.

The spelling of 18691372 in words is "eighteen million, six hundred ninety-one thousand, three hundred seventy-two".