21057338171 has 8 divisors (see below), whose sum is σ = 21317240880. Its totient is φ = 20798604288.

The previous prime is 21057338153. The next prime is 21057338207. The reversal of 21057338171 is 17183375012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21057338171 is a prime.

It is a super-2 number, since 2×21057338171² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21057338111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255926 + ... + 328043.

It is an arithmetic number, because the mean of its divisors is an integer number (2664655110).

Almost surely, 2^21057338171 is an apocalyptic number.

21057338171 is a deficient number, since it is larger than the sum of its proper divisors (259902709).

21057338171 is a wasteful number, since it uses less digits than its factorization.

21057338171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584413.

The product of its (nonzero) digits is 35280, while the sum is 38.

The spelling of 21057338171 in words is "twenty-one billion, fifty-seven million, three hundred thirty-eight thousand, one hundred seventy-one".