121601540 has 24 divisors (see below), whose sum is σ = 258599040. Its totient is φ = 48024288.

The previous prime is 121601521. The next prime is 121601563. The reversal of 121601540 is 45106121.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36902 + ... + 40061.

It is an arithmetic number, because the mean of its divisors is an integer number (10774960).

Almost surely, 2^121601540 is an apocalyptic number.

121601540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121601540 is an abundant number, since it is smaller than the sum of its proper divisors (136997500).

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

121601540 is a wasteful number, since it uses less digits than its factorization.

121601540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77051 (or 77049 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 121601540 is about 11027.3088285402. The cubic root of 121601540 is about 495.4270232752.

Adding to 121601540 its reverse (45106121), we get a palindrome (166707661).

The spelling of 121601540 in words is "one hundred twenty-one million, six hundred one thousand, five hundred forty".