11621634421 has 4 divisors (see below), whose sum is σ = 11622405772. Its totient is φ = 11620863072.

The previous prime is 11621634407. The next prime is 11621634433. The reversal of 11621634421 is 12443612611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12443612611 = 36457 ⋅341323.

It can be written as a sum of positive squares in 2 ways, for example, as 2268616900 + 9353017521 = 47630^2 + 96711^2 .

It is a cyclic number.

It is not a de Polignac number, because 11621634421 - 2⁷ = 11621634293 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 (11621434421) 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, 362616 + ... + 393361.

It is an arithmetic number, because the mean of its divisors is an integer number (2905601443).

Almost surely, 2^11621634421 is an apocalyptic number.

It is an amenable number.

11621634421 is a deficient number, since it is larger than the sum of its proper divisors (771351).

11621634421 is an equidigital number, since it uses as much as digits as its factorization.

11621634421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 771350.

The product of its digits is 6912, while the sum is 31.

The spelling of 11621634421 in words is "eleven billion, six hundred twenty-one million, six hundred thirty-four thousand, four hundred twenty-one".