21675172005 has 12 divisors (see below), whose sum is σ = 37570298220. Its totient is φ = 11560091712.

The previous prime is 21675171979. The next prime is 21675172019. The reversal of 21675172005 is 50027157612.

It can be written as a sum of positive squares in 2 ways, for example, as 9409388004 + 12265784001 = 97002^2 + 110751^2 .

It is not a de Polignac number, because 21675172005 - 2⁶ = 21675171941 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 240835200 + ... + 240835289.

It is an arithmetic number, because the mean of its divisors is an integer number (3130858185).

Almost surely, 2^21675172005 is an apocalyptic number.

It is an amenable number.

21675172005 is a deficient number, since it is larger than the sum of its proper divisors (15895126215).

21675172005 is a wasteful number, since it uses less digits than its factorization.

21675172005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481670500 (or 481670497 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 36.

The spelling of 21675172005 in words is "twenty-one billion, six hundred seventy-five million, one hundred seventy-two thousand, five".