640521501426501 has 16 divisors (see below), whose sum is σ = 893277120278400. Its totient is φ = 407478307199040.

The previous prime is 640521501426481. The next prime is 640521501426511. The reversal of 640521501426501 is 105624105125046.

It is a happy number.

It is not a de Polignac number, because 640521501426501 - 2³⁰ = 640520427684677 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640521501426511) 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 15 ways as a sum of consecutive naturals, for example, 11024816926 + ... + 11024875023.

It is an arithmetic number, because the mean of its divisors is an integer number (55829820017400).

Almost surely, 2^{640521501426501} is an apocalyptic number.

It is an amenable number.

640521501426501 is a deficient number, since it is larger than the sum of its proper divisors (252755618851899).

640521501426501 is a wasteful number, since it uses less digits than its factorization.

640521501426501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22049692396.

The product of its (nonzero) digits is 288000, while the sum is 42.

The spelling of 640521501426501 in words is "six hundred forty trillion, five hundred twenty-one billion, five hundred one million, four hundred twenty-six thousand, five hundred one".