121501521520 has 40 divisors (see below), whose sum is σ = 291603657600. Its totient is φ = 47032846080.

The previous prime is 121501521487. The next prime is 121501521521. The reversal of 121501521520 is 25125105121.

It is a happy number.

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

It is a super-2 number, since 2×121501521520² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121501521521) 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, 24493795 + ... + 24498754.

It is an arithmetic number, because the mean of its divisors is an integer number (7290091440).

Almost surely, 2^121501521520 is an apocalyptic number.

121501521520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121501521520 is an abundant number, since it is smaller than the sum of its proper divisors (170102136080).

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

121501521520 is a wasteful number, since it uses less digits than its factorization.

121501521520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48992593 (or 48992587 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 25.

Adding to 121501521520 its reverse (25125105121), we get a palindrome (146626626641).

The spelling of 121501521520 in words is "one hundred twenty-one billion, five hundred one million, five hundred twenty-one thousand, five hundred twenty".