642642636901 has 16 divisors (see below), whose sum is σ = 716321612160. Its totient is φ = 572955586560.

The previous prime is 642642636869. The next prime is 642642636907. The reversal of 642642636901 is 109636246246.

It is a cyclic number.

It is not a de Polignac number, because 642642636901 - 2⁵ = 642642636869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642642636907) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3825096 + ... + 3989566.

It is an arithmetic number, because the mean of its divisors is an integer number (44770100760).

Almost surely, 2^642642636901 is an apocalyptic number.

It is an amenable number.

642642636901 is a deficient number, since it is larger than the sum of its proper divisors (73678975259).

642642636901 is a wasteful number, since it uses less digits than its factorization.

642642636901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176604.

The product of its (nonzero) digits is 2239488, while the sum is 49.

The spelling of 642642636901 in words is "six hundred forty-two billion, six hundred forty-two million, six hundred thirty-six thousand, nine hundred one".