642226871 has 24 divisors (see below), whose sum is σ = 779237424. Its totient is φ = 524309760.

The previous prime is 642226831. The next prime is 642226873. The reversal of 642226871 is 178622246.

It is a de Polignac number, because none of the positive numbers 2^k-642226871 is a prime.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642226873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 64115 + ... + 73451.

It is an arithmetic number, because the mean of its divisors is an integer number (32468226).

Almost surely, 2^642226871 is an apocalyptic number.

642226871 is a deficient number, since it is larger than the sum of its proper divisors (137010553).

642226871 is a wasteful number, since it uses less digits than its factorization.

642226871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9411 (or 9398 counting only the distinct ones).

The product of its digits is 64512, while the sum is 38.

The square root of 642226871 is about 25342.1954652710. The cubic root of 642226871 is about 862.7722290157.

The spelling of 642226871 in words is "six hundred forty-two million, two hundred twenty-six thousand, eight hundred seventy-one".