105716551621 has 4 divisors (see below), whose sum is σ = 106217578144. Its totient is φ = 105215525100.

The previous prime is 105716551613. The next prime is 105716551687. The reversal of 105716551621 is 126155617501.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 126155617501 = 53593 ⋅2353957.

It is a cyclic number.

It is not a de Polignac number, because 105716551621 - 2³ = 105716551613 is a prime.

It is a super-2 number, since 2×105716551621² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105716551691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250512945 + ... + 250513366.

It is an arithmetic number, because the mean of its divisors is an integer number (26554394536).

Almost surely, 2^105716551621 is an apocalyptic number.

It is an amenable number.

105716551621 is a deficient number, since it is larger than the sum of its proper divisors (501026523).

105716551621 is an equidigital number, since it uses as much as digits as its factorization.

105716551621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501026522.

The product of its (nonzero) digits is 63000, while the sum is 40.

The spelling of 105716551621 in words is "one hundred five billion, seven hundred sixteen million, five hundred fifty-one thousand, six hundred twenty-one".