642656162066 has 8 divisors (see below), whose sum is σ = 964160265420. Its totient is φ = 321269406928.

The previous prime is 642656162053. The next prime is 642656162069. The reversal of 642656162066 is 660261656246.

It can be written as a sum of positive squares in 2 ways, for example, as 636716223025 + 5939939041 = 797945^2 + 77071^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (642656162069) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29323361 + ... + 29345268.

Almost surely, 2^642656162066 is an apocalyptic number.

642656162066 is a deficient number, since it is larger than the sum of its proper divisors (321504103354).

642656162066 is a wasteful number, since it uses less digits than its factorization.

642656162066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58674108.

The product of its (nonzero) digits is 3732480, while the sum is 50.

The spelling of 642656162066 in words is "six hundred forty-two billion, six hundred fifty-six million, one hundred sixty-two thousand, sixty-six".