21113421156 has 18 divisors (see below), whose sum is σ = 53370036902. Its totient is φ = 7037807040.

The previous prime is 21113421107. The next prime is 21113421157. The reversal of 21113421156 is 65112431112.

21113421156 is a `hidden beast` number, since 211 + 13 + 421 + 15 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16983302400 + 4130118756 = 130320^2 + 64266^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (21113421157) 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 5 ways as a sum of consecutive naturals, for example, 293241925 + ... + 293241996.

Almost surely, 2^21113421156 is an apocalyptic number.

It is an amenable number.

21113421156 is an abundant number, since it is smaller than the sum of its proper divisors (32256615746).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21113421156 is a wasteful number, since it uses less digits than its factorization.

21113421156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586483931 (or 586483926 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

Adding to 21113421156 its reverse (65112431112), we get a palindrome (86225852268).

The spelling of 21113421156 in words is "twenty-one billion, one hundred thirteen million, four hundred twenty-one thousand, one hundred fifty-six".