642954811 has 4 divisors (see below), whose sum is σ = 670909392. Its totient is φ = 615000232.

The previous prime is 642954803. The next prime is 642954833. The reversal of 642954811 is 118459246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 642954811 - 2³ = 642954803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642954881) 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, 13977256 + ... + 13977301.

It is an arithmetic number, because the mean of its divisors is an integer number (167727348).

Almost surely, 2^642954811 is an apocalyptic number.

642954811 is a deficient number, since it is larger than the sum of its proper divisors (27954581).

642954811 is a wasteful number, since it uses less digits than its factorization.

642954811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27954580.

The product of its digits is 69120, while the sum is 40.

The square root of 642954811 is about 25356.5536104574. The cubic root of 642954811 is about 863.0980792228.

The spelling of 642954811 in words is "six hundred forty-two million, nine hundred fifty-four thousand, eight hundred eleven".