764651242620021 has 64 divisors (see below), whose sum is σ = 1081910178374400. Its totient is φ = 479021601816576.

The previous prime is 764651242620019. The next prime is 764651242620043. The reversal of 764651242620021 is 120026242156467.

It is not a de Polignac number, because 764651242620021 - 2¹ = 764651242620019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (764651242620821) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 63126489661 + ... + 63126501773.

It is an arithmetic number, because the mean of its divisors is an integer number (16904846537100).

Almost surely, 2^{764651242620021} is an apocalyptic number.

It is an amenable number.

764651242620021 is a deficient number, since it is larger than the sum of its proper divisors (317258935754379).

764651242620021 is a wasteful number, since it uses less digits than its factorization.

764651242620021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18198.

The product of its (nonzero) digits is 1935360, while the sum is 48.

Adding to 764651242620021 its reverse (120026242156467), we get a palindrome (884677484776488).

The spelling of 764651242620021 in words is "seven hundred sixty-four trillion, six hundred fifty-one billion, two hundred forty-two million, six hundred twenty thousand, twenty-one".