21631349205001 has 4 divisors (see below), whose sum is σ = 21699586899972. Its totient is φ = 21563111510032.

The previous prime is 21631349204963. The next prime is 21631349205061. The reversal of 21631349205001 is 10050294313612.

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 8313557288976 + 13317791916025 = 2883324^2 + 3649355^2 .

It is a cyclic number.

It is not a de Polignac number, because 21631349205001 - 2⁹ = 21631349204489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21631349205061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34118847010 + ... + 34118847643.

It is an arithmetic number, because the mean of its divisors is an integer number (5424896724993).

Almost surely, 2^{21631349205001} is an apocalyptic number.

It is an amenable number.

21631349205001 is a deficient number, since it is larger than the sum of its proper divisors (68237694971).

21631349205001 is an equidigital number, since it uses as much as digits as its factorization.

21631349205001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68237694970.

The product of its (nonzero) digits is 38880, while the sum is 37.

The spelling of 21631349205001 in words is "twenty-one trillion, six hundred thirty-one billion, three hundred forty-nine million, two hundred five thousand, one".