121621320 has 48 divisors (see below), whose sum is σ = 395270460. Its totient is φ = 32432256.

The previous prime is 121621319. The next prime is 121621333. The reversal of 121621320 is 23126121.

121621320 is a `hidden beast` number, since 1 + 21 + 621 + 3 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 108618084 + 13003236 = 10422^2 + 3606^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 121621293 and 121621302.

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, 168559 + ... + 169278.

Almost surely, 2^121621320 is an apocalyptic number.

121621320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121621320 is an abundant number, since it is smaller than the sum of its proper divisors (273649140).

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

121621320 is a wasteful number, since it uses less digits than its factorization.

121621320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337854 (or 337847 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 121621320 is about 11028.2056564067. The cubic root of 121621320 is about 495.4538842707.

Adding to 121621320 its reverse (23126121), we get a palindrome (144747441).

The spelling of 121621320 in words is "one hundred twenty-one million, six hundred twenty-one thousand, three hundred twenty".