21530355325031 has 4 divisors (see below), whose sum is σ = 24606120371472. Its totient is φ = 18454590278592.

The previous prime is 21530355324991. The next prime is 21530355325049. The reversal of 21530355325031 is 13052355303512.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21530355325031 is a prime.

It is a super-2 number, since 2×21530355325031² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21530355325931) 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, 1537882523210 + ... + 1537882523223.

It is an arithmetic number, because the mean of its divisors is an integer number (6151530092868).

Almost surely, 2^{21530355325031} is an apocalyptic number.

21530355325031 is a deficient number, since it is larger than the sum of its proper divisors (3075765046441).

21530355325031 is an equidigital number, since it uses as much as digits as its factorization.

21530355325031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3075765046440.

The product of its (nonzero) digits is 202500, while the sum is 38.

The spelling of 21530355325031 in words is "twenty-one trillion, five hundred thirty billion, three hundred fifty-five million, three hundred twenty-five thousand, thirty-one".