20247437250521 has 12 divisors (see below), whose sum is σ = 21924886739580. Its totient is φ = 18689816770560.

The previous prime is 20247437250511. The next prime is 20247437250587. The reversal of 20247437250521 is 12505273474202.

It can be written as a sum of positive squares in 6 ways, for example, as 1555096291225 + 18692340959296 = 1247035^2 + 4323464^2 .

It is not a de Polignac number, because 20247437250521 - 2⁶ = 20247437250457 is a prime.

It is a super-2 number, since 2×20247437250521² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20247437250511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33145985 + ... + 33751313.

It is an arithmetic number, because the mean of its divisors is an integer number (1827073894965).

Almost surely, 2^{20247437250521} is an apocalyptic number.

It is an amenable number.

20247437250521 is a deficient number, since it is larger than the sum of its proper divisors (1677449489059).

20247437250521 is a wasteful number, since it uses less digits than its factorization.

20247437250521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 803276 (or 803263 counting only the distinct ones).

The product of its (nonzero) digits is 940800, while the sum is 44.

The spelling of 20247437250521 in words is "twenty trillion, two hundred forty-seven billion, four hundred thirty-seven million, two hundred fifty thousand, five hundred twenty-one".