643245996 has 24 divisors (see below), whose sum is σ = 1502230464. Its totient is φ = 214226320.

The previous prime is 643245989. The next prime is 643246003. The reversal of 643245996 is 699542346.

It is an interprime number because it is at equal distance from previous prime (643245989) and next prime (643246003).

It is a super-2 number, since 2×643245996² = 827530822740064032, which contains 22 as substring.

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, 9090 + ... + 37001.

It is an arithmetic number, because the mean of its divisors is an integer number (62592936).

Almost surely, 2^643245996 is an apocalyptic number.

It is an amenable number.

643245996 is an abundant number, since it is smaller than the sum of its proper divisors (858984468).

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

643245996 is a wasteful number, since it uses less digits than its factorization.

643245996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47261 (or 47259 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 48.

The square root of 643245996 is about 25362.2947699927. The cubic root of 643245996 is about 863.2283544664.

The spelling of 643245996 in words is "six hundred forty-three million, two hundred forty-five thousand, nine hundred ninety-six".