643131136 has 36 divisors (see below), whose sum is σ = 1285402104. Its totient is φ = 321152000.

The previous prime is 643131109. The next prime is 643131143. The reversal of 643131136 is 631131346.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 332091 + ... + 334021.

It is an arithmetic number, because the mean of its divisors is an integer number (35705614).

Almost surely, 2^643131136 is an apocalyptic number.

It is an amenable number.

643131136 is a deficient number, since it is larger than the sum of its proper divisors (642270968).

643131136 is a wasteful number, since it uses less digits than its factorization.

643131136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3248 (or 3234 counting only the distinct ones).

The product of its digits is 3888, while the sum is 28.

The square root of 643131136 is about 25360.0302838936. The cubic root of 643131136 is about 863.1769711638.

The spelling of 643131136 in words is "six hundred forty-three million, one hundred thirty-one thousand, one hundred thirty-six".