1620643212 has 18 divisors (see below), whose sum is σ = 4096625988. Its totient is φ = 540214392.

The previous prime is 1620643207. The next prime is 1620643223. The reversal of 1620643212 is 2123460261.

1620643212 is a `hidden beast` number, since 1 + 6 + 2 + 0 + 643 + 2 + 12 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22508898 + ... + 22508969.

Almost surely, 2^1620643212 is an apocalyptic number.

1620643212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1620643212 is an abundant number, since it is smaller than the sum of its proper divisors (2475982776).

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

1620643212 is a wasteful number, since it uses less digits than its factorization.

1620643212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45017877 (or 45017872 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 1620643212 is about 40257.2131673319. The cubic root of 1620643212 is about 1174.6157094281.

The spelling of 1620643212 in words is "one billion, six hundred twenty million, six hundred forty-three thousand, two hundred twelve".