21122120100 has 36 divisors (see below), whose sum is σ = 61113335024. Its totient is φ = 5632565280.

The previous prime is 21122120077. The next prime is 21122120119. The reversal of 21122120100 is 102122112.

It is a super-2 number, since 2×21122120100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35203234 + ... + 35203833.

Almost surely, 2^21122120100 is an apocalyptic number.

21122120100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122120100 is an abundant number, since it is smaller than the sum of its proper divisors (39991214924).

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

21122120100 is a wasteful number, since it uses less digits than its factorization.

21122120100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70407084 (or 70407077 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21122120100 its reverse (102122112), we get a palindrome (21224242212).

It can be divided in two parts, 2112 and 2120100, that added together give a palindrome (2122212).

The spelling of 21122120100 in words is "twenty-one billion, one hundred twenty-two million, one hundred twenty thousand, one hundred".