21113522413 has 4 divisors (see below), whose sum is σ = 21841574940. Its totient is φ = 20385469888.

The previous prime is 21113522389. The next prime is 21113522429. The reversal of 21113522413 is 31422531112.

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 12078449604 + 9035072809 = 109902^2 + 95053^2 .

It is a cyclic number.

It is not a de Polignac number, because 21113522413 - 2²¹ = 21111425261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113522473) 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, 364026220 + ... + 364026277.

It is an arithmetic number, because the mean of its divisors is an integer number (5460393735).

Almost surely, 2^21113522413 is an apocalyptic number.

It is an amenable number.

21113522413 is a deficient number, since it is larger than the sum of its proper divisors (728052527).

21113522413 is an equidigital number, since it uses as much as digits as its factorization.

21113522413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728052526.

The product of its digits is 1440, while the sum is 25.

The spelling of 21113522413 in words is "twenty-one billion, one hundred thirteen million, five hundred twenty-two thousand, four hundred thirteen".