2161654362651 has 16 divisors (see below), whose sum is σ = 3293970166784. Its totient is φ = 1235223316224.

The previous prime is 2161654362457. The next prime is 2161654362691. The reversal of 2161654362651 is 1562634561612.

It is a happy number.

It is not a de Polignac number, because 2161654362651 - 2²² = 2161650168347 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2161654362651.

It is not an unprimeable number, because it can be changed into a prime (2161654362691) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5846091 + ... + 6204843.

It is an arithmetic number, because the mean of its divisors is an integer number (205873135424).

Almost surely, 2^{2161654362651} is an apocalyptic number.

2161654362651 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2161654362651 is a deficient number, since it is larger than the sum of its proper divisors (1132315804133).

2161654362651 is a wasteful number, since it uses less digits than its factorization.

2161654362651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645690.

The product of its digits is 1555200, while the sum is 48.

The spelling of 2161654362651 in words is "two trillion, one hundred sixty-one billion, six hundred fifty-four million, three hundred sixty-two thousand, six hundred fifty-one".