40520661503521 has 4 divisors (see below), whose sum is σ = 40527382468500. Its totient is φ = 40513940538544.

The previous prime is 40520661503503. The next prime is 40520661503599. The reversal of 40520661503521 is 12530516602504.

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 36589324285921 + 3931337217600 = 6048911^2 + 1982760^2 .

It is a cyclic number.

It is not a de Polignac number, because 40520661503521 - 2²⁹ = 40520124632609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40520661503221) 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, 3360473446 + ... + 3360485503.

It is an arithmetic number, because the mean of its divisors is an integer number (10131845617125).

Almost surely, 2^{40520661503521} is an apocalyptic number.

It is an amenable number.

40520661503521 is a deficient number, since it is larger than the sum of its proper divisors (6720964979).

40520661503521 is an equidigital number, since it uses as much as digits as its factorization.

40520661503521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6720964978.

The product of its (nonzero) digits is 216000, while the sum is 40.

The spelling of 40520661503521 in words is "forty trillion, five hundred twenty billion, six hundred sixty-one million, five hundred three thousand, five hundred twenty-one".