639616057601 has 4 divisors (see below), whose sum is σ = 650101566804. Its totient is φ = 629130548400.

The previous prime is 639616057571. The next prime is 639616057621. The reversal of 639616057601 is 106750616936.

It is a happy number.

It is a Cunningham number, because it is equal to 799760²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20799408400 + 618816649201 = 144220^2 + 786649^2 .

It is a cyclic number.

It is not a de Polignac number, because 639616057601 - 2¹⁰ = 639616056577 is a prime.

It is a super-2 number, since 2×639616057601² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 639616057601.

It is not an unprimeable number, because it can be changed into a prime (639616057621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5242754510 + ... + 5242754631.

It is an arithmetic number, because the mean of its divisors is an integer number (162525391701).

Almost surely, 2^639616057601 is an apocalyptic number.

639616057601 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

639616057601 is a deficient number, since it is larger than the sum of its proper divisors (10485509203).

639616057601 is a wasteful number, since it uses less digits than its factorization.

639616057601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10485509202.

The product of its (nonzero) digits is 1224720, while the sum is 50.

The spelling of 639616057601 in words is "six hundred thirty-nine billion, six hundred sixteen million, fifty-seven thousand, six hundred one".