11553321421 has 16 divisors (see below), whose sum is σ = 11846887920. Its totient is φ = 11263795200.

The previous prime is 11553321391. The next prime is 11553321449. The reversal of 11553321421 is 12412335511.

It can be written as a sum of positive squares in 8 ways, for example, as 81225 + 11553240196 = 285^2 + 107486^2 .

It is a cyclic number.

It is not a de Polignac number, because 11553321421 - 2⁵ = 11553321389 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11553321421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11553321491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7438581 + ... + 7440133.

It is an arithmetic number, because the mean of its divisors is an integer number (740430495).

Almost surely, 2^11553321421 is an apocalyptic number.

It is an amenable number.

11553321421 is a deficient number, since it is larger than the sum of its proper divisors (293566499).

11553321421 is a wasteful number, since it uses less digits than its factorization.

11553321421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2736.

The product of its digits is 3600, while the sum is 28.

Adding to 11553321421 its reverse (12412335511), we get a palindrome (23965656932).

The spelling of 11553321421 in words is "eleven billion, five hundred fifty-three million, three hundred twenty-one thousand, four hundred twenty-one".