21401111220 has 48 divisors (see below), whose sum is σ = 60118352448. Its totient is φ = 5688368640.

The previous prime is 21401111219. The next prime is 21401111287. The reversal of 21401111220 is 2211110412.

It is a super-2 number, since 2×21401111220² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21401111220.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 562501 + ... + 599340.

It is an arithmetic number, because the mean of its divisors is an integer number (1252465676).

Almost surely, 2^21401111220 is an apocalyptic number.

21401111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21401111220 is an abundant number, since it is smaller than the sum of its proper divisors (38717241228).

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

21401111220 is a wasteful number, since it uses less digits than its factorization.

21401111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1162160 (or 1162158 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21401111220 its reverse (2211110412), we get a palindrome (23612221632).

The spelling of 21401111220 in words is "twenty-one billion, four hundred one million, one hundred eleven thousand, two hundred twenty".