121555115601 has 8 divisors (see below), whose sum is σ = 162135334464. Its totient is φ = 81005820240.

The previous prime is 121555115581. The next prime is 121555115603. The reversal of 121555115601 is 106511555121.

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

It is not a de Polignac number, because 121555115601 - 2⁵ = 121555115569 is a prime.

It is a super-2 number, since 2×121555115601² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121555115603) 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, 7721701 + ... + 7737426.

It is an arithmetic number, because the mean of its divisors is an integer number (20266916808).

Almost surely, 2^121555115601 is an apocalyptic number.

It is an amenable number.

121555115601 is a deficient number, since it is larger than the sum of its proper divisors (40580218863).

121555115601 is a wasteful number, since it uses less digits than its factorization.

121555115601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15461751.

The product of its (nonzero) digits is 7500, while the sum is 33.

The spelling of 121555115601 in words is "one hundred twenty-one billion, five hundred fifty-five million, one hundred fifteen thousand, six hundred one".