21123130331 has 8 divisors (see below), whose sum is σ = 22008305664. Its totient is φ = 20250691560.

The previous prime is 21123130291. The next prime is 21123130339. The reversal of 21123130331 is 13303132112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21123130331 is a prime.

It is a super-2 number, since 2×21123130331² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21123130339) 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 7 ways as a sum of consecutive naturals, for example, 3180755 + ... + 3187388.

It is an arithmetic number, because the mean of its divisors is an integer number (2751038208).

Almost surely, 2^21123130331 is an apocalyptic number.

21123130331 is a deficient number, since it is larger than the sum of its proper divisors (885175333).

21123130331 is a wasteful number, since it uses less digits than its factorization.

21123130331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6368281.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 21123130331 its reverse (13303132112), we get a palindrome (34426262443).

The spelling of 21123130331 in words is "twenty-one billion, one hundred twenty-three million, one hundred thirty thousand, three hundred thirty-one".