121515552 has 84 divisors (see below), whose sum is σ = 358755390. Its totient is φ = 40497408.

The previous prime is 121515551. The next prime is 121515553. The reversal of 121515552 is 255515121.

It is an interprime number because it is at equal distance from previous prime (121515551) and next prime (121515553).

It can be written as a sum of positive squares in only one way, i.e., 69155856 + 52359696 = 8316^2 + 7236^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (121515551) by changing a digit.

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 13 ways as a sum of consecutive naturals, for example, 20724 + ... + 25932.

Almost surely, 2^121515552 is an apocalyptic number.

121515552 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121515552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179377695).

121515552 is an abundant number, since it is smaller than the sum of its proper divisors (237239838).

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

121515552 is an frugal number, since it uses more digits than its factorization.

121515552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5237 (or 5214 counting only the distinct ones).

The product of its digits is 2500, while the sum is 27.

The square root of 121515552 is about 11023.4092729972. The cubic root of 121515552 is about 495.3102187670.

The spelling of 121515552 in words is "one hundred twenty-one million, five hundred fifteen thousand, five hundred fifty-two".