21621337442131 has 4 divisors (see below), whose sum is σ = 24710099933872. Its totient is φ = 18532574950392.

The previous prime is 21621337442101. The next prime is 21621337442137. The reversal of 21621337442131 is 13124473312612.

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

It is a cyclic number.

It is not a de Polignac number, because 21621337442131 - 2⁹ = 21621337441619 is a prime.

It is a super-2 number, since 2×21621337442131² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21621337442137) 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, 1544381245860 + ... + 1544381245873.

It is an arithmetic number, because the mean of its divisors is an integer number (6177524983468).

Almost surely, 2^{21621337442131} is an apocalyptic number.

21621337442131 is a deficient number, since it is larger than the sum of its proper divisors (3088762491741).

21621337442131 is an equidigital number, since it uses as much as digits as its factorization.

21621337442131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3088762491740.

The product of its digits is 145152, while the sum is 40.

The spelling of 21621337442131 in words is "twenty-one trillion, six hundred twenty-one billion, three hundred thirty-seven million, four hundred forty-two thousand, one hundred thirty-one".