421866978 has 32 divisors (see below), whose sum is σ = 914760000. Its totient is φ = 128930496.

The previous prime is 421866947. The next prime is 421866997. The reversal of 421866978 is 879668124.

It is a self number, because there is not a number n which added to its sum of digits gives 421866978.

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, 6528 + ... + 29771.

It is an arithmetic number, because the mean of its divisors is an integer number (28586250).

Almost surely, 2^421866978 is an apocalyptic number.

421866978 is an abundant number, since it is smaller than the sum of its proper divisors (492893022).

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

421866978 is a wasteful number, since it uses less digits than its factorization.

421866978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36466.

The product of its digits is 1161216, while the sum is 51.

The square root of 421866978 is about 20539.4006241662. The cubic root of 421866978 is about 749.9952461921.

It can be divided in two parts, 42186697 and 8, that added together give a triangular number (42186705 = T₉₁₈₅).

The spelling of 421866978 in words is "four hundred twenty-one million, eight hundred sixty-six thousand, nine hundred seventy-eight".