2161121346521 has 8 divisors (see below), whose sum is σ = 2163346315200. Its totient is φ = 2158896584080.

The previous prime is 2161121346473. The next prime is 2161121346523. The reversal of 2161121346521 is 1256431211612.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 2161121346521 - 2²² = 2161117152217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2161121346523) 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, 29535860 + ... + 29608938.

It is an arithmetic number, because the mean of its divisors is an integer number (270418289400).

Almost surely, 2^{2161121346521} is an apocalyptic number.

It is an amenable number.

2161121346521 is a deficient number, since it is larger than the sum of its proper divisors (2224968679).

2161121346521 is a wasteful number, since it uses less digits than its factorization.

2161121346521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103119.

The product of its digits is 17280, while the sum is 35.

The spelling of 2161121346521 in words is "two trillion, one hundred sixty-one billion, one hundred twenty-one million, three hundred forty-six thousand, five hundred twenty-one".