121537440 has 72 divisors (see below), whose sum is σ = 414751428. Its totient is φ = 32409600.

The previous prime is 121537439. The next prime is 121537457. The reversal of 121537440 is 44735121.

121537440 is a `hidden beast` number, since 1 + 215 + 3 + 7 + 440 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 105760656 + 15776784 = 10284^2 + 3972^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40761 + ... + 43640.

Almost surely, 2^121537440 is an apocalyptic number.

121537440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121537440 is an abundant number, since it is smaller than the sum of its proper divisors (293213988).

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

121537440 is a wasteful number, since it uses less digits than its factorization.

121537440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84422 (or 84411 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 121537440 is about 11024.4020245998. The cubic root of 121537440 is about 495.3399562479.

The spelling of 121537440 in words is "one hundred twenty-one million, five hundred thirty-seven thousand, four hundred forty".