642310819 has 4 divisors (see below), whose sum is σ = 642430096. Its totient is φ = 642191544.

The previous prime is 642310783. The next prime is 642310829. The reversal of 642310819 is 918013246.

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 642310819 - 2²¹ = 640213667 is a prime.

It is a super-2 number, since 2×642310819² = 825126376408901522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642310829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51159 + ... + 62464.

It is an arithmetic number, because the mean of its divisors is an integer number (160607524).

Almost surely, 2^642310819 is an apocalyptic number.

642310819 is a deficient number, since it is larger than the sum of its proper divisors (119277).

642310819 is a wasteful number, since it uses less digits than its factorization.

642310819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119276.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 642310819 is about 25343.8517001659. The cubic root of 642310819 is about 862.8098194950.

The spelling of 642310819 in words is "six hundred forty-two million, three hundred ten thousand, eight hundred nineteen".