1056521615605 has 4 divisors (see below), whose sum is σ = 1267825938732. Its totient is φ = 845217292480.

The previous prime is 1056521615587. The next prime is 1056521615647. The reversal of 1056521615605 is 5065161256501.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 544794562404 + 511727053201 = 738102^2 + 715351^2 .

It is not a de Polignac number, because 1056521615605 - 2¹⁷ = 1056521484533 is a prime.

It is a super-2 number, since 2×1056521615605² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105652161556 + ... + 105652161565.

It is an arithmetic number, because the mean of its divisors is an integer number (316956484683).

Almost surely, 2^{1056521615605} is an apocalyptic number.

It is an amenable number.

1056521615605 is a deficient number, since it is larger than the sum of its proper divisors (211304323127).

1056521615605 is an equidigital number, since it uses as much as digits as its factorization.

1056521615605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211304323126.

The product of its (nonzero) digits is 270000, while the sum is 43.

The spelling of 1056521615605 in words is "one trillion, fifty-six billion, five hundred twenty-one million, six hundred fifteen thousand, six hundred five".