21130414421 has 2 divisors, whose sum is σ = 21130414422. Its totient is φ = 21130414420.

The previous prime is 21130414399. The next prime is 21130414429. The reversal of 21130414421 is 12441403112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13379548900 + 7750865521 = 115670^2 + 88039^2 .

It is a cyclic number.

It is not a de Polignac number, because 21130414421 - 2²² = 21126220117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21130414429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565207210 + 10565207211.

It is an arithmetic number, because the mean of its divisors is an integer number (10565207211).

Almost surely, 2^21130414421 is an apocalyptic number.

It is an amenable number.

21130414421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21130414421 is an equidigital number, since it uses as much as digits as its factorization.

21130414421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 21130414421 its reverse (12441403112), we get a palindrome (33571817533).

The spelling of 21130414421 in words is "twenty-one billion, one hundred thirty million, four hundred fourteen thousand, four hundred twenty-one".