2178451001961 has 16 divisors (see below), whose sum is σ = 3475591342720. Its totient is φ = 1340585231760.

The previous prime is 2178451001939. The next prime is 2178451001971. The reversal of 2178451001961 is 1691001548712.

2178451001961 is a `hidden beast` number, since 2 + 1 + 7 + 8 + 451 + 0 + 0 + 196 + 1 = 666.

It is not a de Polignac number, because 2178451001961 - 2⁹ = 2178451001449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2178451001971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3103206205 + ... + 3103206906.

It is an arithmetic number, because the mean of its divisors is an integer number (217224458920).

Almost surely, 2^{2178451001961} is an apocalyptic number.

It is an amenable number.

2178451001961 is a deficient number, since it is larger than the sum of its proper divisors (1297140340759).

2178451001961 is a wasteful number, since it uses less digits than its factorization.

2178451001961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6206413133 (or 6206413127 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The spelling of 2178451001961 in words is "two trillion, one hundred seventy-eight billion, four hundred fifty-one million, one thousand, nine hundred sixty-one".