121313220 has 72 divisors (see below), whose sum is σ = 395144064. Its totient is φ = 27728064.

The previous prime is 121313197. The next prime is 121313243. The reversal of 121313220 is 22313121.

It is an interprime number because it is at equal distance from previous prime (121313197) and next prime (121313243).

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 121313220.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17692 + ... + 23571.

It is an arithmetic number, because the mean of its divisors is an integer number (5488112).

Almost surely, 2^121313220 is an apocalyptic number.

121313220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121313220 is an abundant number, since it is smaller than the sum of its proper divisors (273830844).

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

121313220 is a wasteful number, since it uses less digits than its factorization.

121313220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41289 (or 41280 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 121313220 is about 11014.2280709998. The cubic root of 121313220 is about 495.0351571805.

Adding to 121313220 its reverse (22313121), we get a palindrome (143626341).

Subtracting from 121313220 its reverse (22313121), we obtain a palindrome (99000099).

It can be divided in two parts, 12131 and 3220, that added together give a palindrome (15351).

The spelling of 121313220 in words is "one hundred twenty-one million, three hundred thirteen thousand, two hundred twenty".