642769780 has 24 divisors (see below), whose sum is σ = 1351703808. Its totient is φ = 256748448.

The previous prime is 642769769. The next prime is 642769783. The reversal of 642769780 is 87967246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642769783) 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 7 ways as a sum of consecutive naturals, for example, 7564 + ... + 36643.

It is an arithmetic number, because the mean of its divisors is an integer number (56320992).

Almost surely, 2^642769780 is an apocalyptic number.

It is an amenable number.

642769780 is an abundant number, since it is smaller than the sum of its proper divisors (708934028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642769780 is a wasteful number, since it uses less digits than its factorization.

642769780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44943 (or 44941 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 49.

The square root of 642769780 is about 25352.9047645433. The cubic root of 642769780 is about 863.0152765022.

The spelling of 642769780 in words is "six hundred forty-two million, seven hundred sixty-nine thousand, seven hundred eighty".