21746345472521 has 8 divisors (see below), whose sum is σ = 22521836968704. Its totient is φ = 20983887447040.

The previous prime is 21746345472479. The next prime is 21746345472539. The reversal of 21746345472521 is 12527454364712.

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-21746345472521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21746345472221) 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, 3258364280 + ... + 3258370953.

It is an arithmetic number, because the mean of its divisors is an integer number (2815229621088).

Almost surely, 2^{21746345472521} is an apocalyptic number.

It is an amenable number.

21746345472521 is a deficient number, since it is larger than the sum of its proper divisors (775491496183).

21746345472521 is an equidigital number, since it uses as much as digits as its factorization.

21746345472521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6516735351.

The product of its digits is 11289600, while the sum is 53.

The spelling of 21746345472521 in words is "twenty-one trillion, seven hundred forty-six billion, three hundred forty-five million, four hundred seventy-two thousand, five hundred twenty-one".