10145664421621 has 4 divisors (see below), whose sum is σ = 10145674082412. Its totient is φ = 10145654760832.

The previous prime is 10145664421609. The next prime is 10145664421643. The reversal of 10145664421621 is 12612446654101.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 9166180104900 + 979484316721 = 3027570^2 + 989689^2 .

It is a cyclic number.

It is not a de Polignac number, because 10145664421621 - 2⁷ = 10145664421493 is a prime.

It is a super-2 number, since 2×10145664421621² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10145664421691) 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, 3031900 + ... + 5429893.

It is an arithmetic number, because the mean of its divisors is an integer number (2536418520603).

Almost surely, 2^{10145664421621} is an apocalyptic number.

It is an amenable number.

10145664421621 is a deficient number, since it is larger than the sum of its proper divisors (9660791).

10145664421621 is an equidigital number, since it uses as much as digits as its factorization.

10145664421621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9660790.

The product of its (nonzero) digits is 276480, while the sum is 43.

The spelling of 10145664421621 in words is "ten trillion, one hundred forty-five billion, six hundred sixty-four million, four hundred twenty-one thousand, six hundred twenty-one".