18919770 has 16 divisors (see below), whose sum is σ = 45407520. Its totient is φ = 5045264.

The previous prime is 18919757. The next prime is 18919807. The reversal of 18919770 is 7791981.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315300 + ... + 315359.

It is an arithmetic number, because the mean of its divisors is an integer number (2837970).

Almost surely, 2^18919770 is an apocalyptic number.

18919770 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18919770 is an abundant number, since it is smaller than the sum of its proper divisors (26487750).

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

18919770 is a wasteful number, since it uses less digits than its factorization.

18919770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630669.

The product of its (nonzero) digits is 31752, while the sum is 42.

The square root of 18919770 is about 4349.6861955778. The cubic root of 18919770 is about 266.4640457346.

The spelling of 18919770 in words is "eighteen million, nine hundred nineteen thousand, seven hundred seventy".