2116561641 has 8 divisors (see below), whose sum is σ = 2822480064. Its totient is φ = 1410842160.

The previous prime is 2116561633. The next prime is 2116561663. The reversal of 2116561641 is 1461656112.

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

It is not a de Polignac number, because 2116561641 - 2³ = 2116561633 is a prime.

It is a super-2 number, since 2×2116561641² = 8959666360305225762, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2116561141) 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, 22830 + ... + 68951.

It is an arithmetic number, because the mean of its divisors is an integer number (352810008).

Almost surely, 2^2116561641 is an apocalyptic number.

It is an amenable number.

2116561641 is a deficient number, since it is larger than the sum of its proper divisors (705918423).

2116561641 is an equidigital number, since it uses as much as digits as its factorization.

2116561641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99471.

The product of its digits is 8640, while the sum is 33.

The square root of 2116561641 is about 46006.1043884396. The cubic root of 2116561641 is about 1283.9367811529.

The spelling of 2116561641 in words is "two billion, one hundred sixteen million, five hundred sixty-one thousand, six hundred forty-one".