18877644 has 48 divisors (see below), whose sum is σ = 49996800. Its totient is φ = 6157008.

The previous prime is 18877631. The next prime is 18877673. The reversal of 18877644 is 44677881.

It is a self number, because there is not a number n which added to its sum of digits gives 18877644.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3217 + ... + 6935.

It is an arithmetic number, because the mean of its divisors is an integer number (1041600).

Almost surely, 2^18877644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18877644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24998400).

18877644 is an abundant number, since it is smaller than the sum of its proper divisors (31119156).

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

18877644 is a wasteful number, since it uses less digits than its factorization.

18877644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3779 (or 3771 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 18877644 is about 4344.8410787968. The cubic root of 18877644 is about 266.2661327261.

The spelling of 18877644 in words is "eighteen million, eight hundred seventy-seven thousand, six hundred forty-four".