121220222100021 has 12 divisors (see below), whose sum is σ = 191013683309280. Its totient is φ = 73466801272680.

The previous prime is 121220222099923. The next prime is 121220222100083. The reversal of 121220222100021 is 120001222022121.

It is a happy number.

121220222100021 is a `hidden beast` number, since 121 + 220 + 222 + 100 + 0 + 2 + 1 = 666.

It is not a de Polignac number, because 121220222100021 - 2¹⁵ = 121220222067253 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121220222099967 and 121220222100003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121220222100121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 612223343841 + ... + 612223344038.

It is an arithmetic number, because the mean of its divisors is an integer number (15917806942440).

Almost surely, 2^{121220222100021} is an apocalyptic number.

121220222100021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121220222100021 is a deficient number, since it is larger than the sum of its proper divisors (69793461209259).

121220222100021 is a wasteful number, since it uses less digits than its factorization.

121220222100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1224446687896 (or 1224446687893 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 121220222100021 its reverse (120001222022121), we get a palindrome (241221444122142).

The spelling of 121220222100021 in words is "one hundred twenty-one trillion, two hundred twenty billion, two hundred twenty-two million, one hundred thousand, twenty-one".