122100021 has 8 divisors (see below), whose sum is σ = 180888960. Its totient is φ = 81399996.

The previous prime is 122100007. The next prime is 122100029. The reversal of 122100021 is 120001221.

It is not a de Polignac number, because 122100021 - 2¹³ = 122091829 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 122099976 and 122100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (122100029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2261085 + ... + 2261138.

It is an arithmetic number, because the mean of its divisors is an integer number (22611120).

Almost surely, 2^122100021 is an apocalyptic number.

It is an amenable number.

122100021 is a deficient number, since it is larger than the sum of its proper divisors (58788939).

122100021 is an equidigital number, since it uses as much as digits as its factorization.

122100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4522232 (or 4522226 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 122100021 is about 11049.8878274849. The cubic root of 122100021 is about 496.1030680821.

Adding to 122100021 its reverse (120001221), we get a palindrome (242101242).

It can be divided in two parts, 12 and 2100021, that multiplied together give a palindrome (25200252).

The spelling of 122100021 in words is "one hundred twenty-two million, one hundred thousand, twenty-one".