21617375745 has 32 divisors (see below), whose sum is σ = 39558094848. Its totient is φ = 9874934208.

The previous prime is 21617375713. The next prime is 21617375783. The reversal of 21617375745 is 54757371612.

It is not a de Polignac number, because 21617375745 - 2⁵ = 21617375713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21617375694 and 21617375703.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68232 + ... + 218838.

It is an arithmetic number, because the mean of its divisors is an integer number (1236190464).

Almost surely, 2^21617375745 is an apocalyptic number.

It is an amenable number.

21617375745 is a deficient number, since it is larger than the sum of its proper divisors (17940719103).

21617375745 is a wasteful number, since it uses less digits than its factorization.

21617375745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151989.

The product of its digits is 1234800, while the sum is 48.

The spelling of 21617375745 in words is "twenty-one billion, six hundred seventeen million, three hundred seventy-five thousand, seven hundred forty-five".