121165021156165 has 32 divisors (see below), whose sum is σ = 167978032911360. Its totient is φ = 82181132734464.

The previous prime is 121165021156159. The next prime is 121165021156241. The reversal of 121165021156165 is 561651120561121.

It is a cyclic number.

It is not a de Polignac number, because 121165021156165 - 2¹⁷ = 121165021025093 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4228045 + ... + 16130914.

It is an arithmetic number, because the mean of its divisors is an integer number (5249313528480).

Almost surely, 2^{121165021156165} is an apocalyptic number.

It is an amenable number.

121165021156165 is a deficient number, since it is larger than the sum of its proper divisors (46813011755195).

121165021156165 is a wasteful number, since it uses less digits than its factorization.

121165021156165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20360821.

The product of its (nonzero) digits is 108000, while the sum is 43.

The spelling of 121165021156165 in words is "one hundred twenty-one trillion, one hundred sixty-five billion, twenty-one million, one hundred fifty-six thousand, one hundred sixty-five".