2475661666721 has 4 divisors (see below), whose sum is σ = 2605959649200. Its totient is φ = 2345363684244.

The previous prime is 2475661666717. The next prime is 2475661666757. The reversal of 2475661666721 is 1276661665742.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 2475661666721 - 2² = 2475661666717 is a prime.

It is a super-2 number, since 2×2475661666721² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2475661666771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65148991211 + ... + 65148991248.

It is an arithmetic number, because the mean of its divisors is an integer number (651489912300).

Almost surely, 2^{2475661666721} is an apocalyptic number.

It is an amenable number.

2475661666721 is a deficient number, since it is larger than the sum of its proper divisors (130297982479).

2475661666721 is a wasteful number, since it uses less digits than its factorization.

2475661666721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130297982478.

The product of its digits is 30481920, while the sum is 59.

The spelling of 2475661666721 in words is "two trillion, four hundred seventy-five billion, six hundred sixty-one million, six hundred sixty-six thousand, seven hundred twenty-one".