121655615 has 8 divisors (see below), whose sum is σ = 146119248. Its totient is φ = 97236160.

The previous prime is 121655549. The next prime is 121655627. The reversal of 121655615 is 516556121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121655615 - 2²⁴ = 104878399 is a prime.

It is a super-2 number, since 2×121655615² = 29600177322056450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 4646 + ... + 16275.

It is an arithmetic number, because the mean of its divisors is an integer number (18264906).

Almost surely, 2^121655615 is an apocalyptic number.

121655615 is a deficient number, since it is larger than the sum of its proper divisors (24463633).

121655615 is a wasteful number, since it uses less digits than its factorization.

121655615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22089.

The product of its digits is 9000, while the sum is 32.

The square root of 121655615 is about 11029.7604235088. The cubic root of 121655615 is about 495.5004495552.

The spelling of 121655615 in words is "one hundred twenty-one million, six hundred fifty-five thousand, six hundred fifteen".