121437520 has 40 divisors (see below), whose sum is σ = 282872520. Its totient is φ = 48483840.

The previous prime is 121437499. The next prime is 121437521. The reversal of 121437520 is 25734121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 18455616 + 102981904 = 4296^2 + 10148^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121437521) 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, 55650 + ... + 57790.

It is an arithmetic number, because the mean of its divisors is an integer number (7071813).

Almost surely, 2^121437520 is an apocalyptic number.

121437520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121437520 is an abundant number, since it is smaller than the sum of its proper divisors (161435000).

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

121437520 is a wasteful number, since it uses less digits than its factorization.

121437520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2863 (or 2857 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 121437520 is about 11019.8693277189. The cubic root of 121437520 is about 495.2041738412.

The spelling of 121437520 in words is "one hundred twenty-one million, four hundred thirty-seven thousand, five hundred twenty".