642869716 has 6 divisors (see below), whose sum is σ = 1125022010. Its totient is φ = 321434856.

The previous prime is 642869681. The next prime is 642869719. The reversal of 642869716 is 617968246.

It can be written as a sum of positive squares in only one way, i.e., 423948100 + 218921616 = 20590^2 + 14796^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 642869716.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642869719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80358711 + ... + 80358718.

Almost surely, 2^642869716 is an apocalyptic number.

It is an amenable number.

642869716 is a deficient number, since it is larger than the sum of its proper divisors (482152294).

642869716 is a wasteful number, since it uses less digits than its factorization.

642869716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160717433 (or 160717431 counting only the distinct ones).

The product of its digits is 870912, while the sum is 49.

The square root of 642869716 is about 25354.8755863641. The cubic root of 642869716 is about 863.0600005636.

The spelling of 642869716 in words is "six hundred forty-two million, eight hundred sixty-nine thousand, seven hundred sixteen".