421640661420 has 144 divisors (see below), whose sum is σ = 1395475361280. Its totient is φ = 102199209600.

The previous prime is 421640661413. The next prime is 421640661439. The reversal of 421640661420 is 24166046124.

421640661420 is a `hidden beast` number, since 4 + 2 + 1 + 640 + 6 + 6 + 1 + 4 + 2 + 0 = 666.

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 47 ways as a sum of consecutive naturals, for example, 15666175 + ... + 15693065.

It is an arithmetic number, because the mean of its divisors is an integer number (9690801120).

Almost surely, 2^421640661420 is an apocalyptic number.

It is an amenable number.

421640661420 is an abundant number, since it is smaller than the sum of its proper divisors (973834699860).

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

421640661420 is a wasteful number, since it uses less digits than its factorization.

421640661420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34836 (or 34831 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The spelling of 421640661420 in words is "four hundred twenty-one billion, six hundred forty million, six hundred sixty-one thousand, four hundred twenty".