646440620 has 24 divisors (see below), whose sum is σ = 1551457824. Its totient is φ = 221636736.

The previous prime is 646440611. The next prime is 646440637. The reversal of 646440620 is 26044646.

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, 2308577 + ... + 2308856.

It is an arithmetic number, because the mean of its divisors is an integer number (64644076).

Almost surely, 2^646440620 is an apocalyptic number.

It is an amenable number.

646440620 is an abundant number, since it is smaller than the sum of its proper divisors (905017204).

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

646440620 is a wasteful number, since it uses less digits than its factorization.

646440620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4617449 (or 4617447 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

The square root of 646440620 is about 25425.1965577456. The cubic root of 646440620 is about 864.6550441602.

The spelling of 646440620 in words is "six hundred forty-six million, four hundred forty thousand, six hundred twenty".