21955637601 has 8 divisors (see below), whose sum is σ = 32526870560. Its totient is φ = 14637091716.

The previous prime is 21955637537. The next prime is 21955637611. The reversal of 21955637601 is 10673655912.

21955637601 is a `hidden beast` number, since 2 + 1 + 9 + 5 + 5 + 6 + 37 + 601 = 666.

It is not a de Polignac number, because 21955637601 - 2⁶ = 21955637537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21955637611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406585855 + ... + 406585908.

It is an arithmetic number, because the mean of its divisors is an integer number (4065858820).

Almost surely, 2^21955637601 is an apocalyptic number.

It is an amenable number.

21955637601 is a deficient number, since it is larger than the sum of its proper divisors (10571232959).

21955637601 is an equidigital number, since it uses as much as digits as its factorization.

21955637601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 813171772 (or 813171766 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 45.

The spelling of 21955637601 in words is "twenty-one billion, nine hundred fifty-five million, six hundred thirty-seven thousand, six hundred one".