6543920636 has 36 divisors (see below), whose sum is σ = 13271072136. Its totient is φ = 2799532800.

The previous prime is 6543920633. The next prime is 6543920641. The reversal of 6543920636 is 6360293456.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6543920633) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 244595 + ... + 270026.

Almost surely, 2^6543920636 is an apocalyptic number.

It is an amenable number.

6543920636 is an abundant number, since it is smaller than the sum of its proper divisors (6727151500).

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

6543920636 is a wasteful number, since it uses less digits than its factorization.

6543920636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514670 (or 514651 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 44.

The square root of 6543920636 is about 80894.5031259850. The cubic root of 6543920636 is about 1870.4495888700.

The spelling of 6543920636 in words is "six billion, five hundred forty-three million, nine hundred twenty thousand, six hundred thirty-six".