20862624721 has 3 divisors (see below), whose sum is σ = 20862769161. Its totient is φ = 20862480282.

The previous prime is 20862624709. The next prime is 20862624767. The reversal of 20862624721 is 12742626802.

The square root of 20862624721 is 144439.

It is a perfect power (a square), and thus also a powerful 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 is not a de Polignac number, because 20862624721 - 2²³ = 20854236113 is a prime.

It is a super-2 number, since 2×20862624721² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20862624221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 72220 + ... + 216658.

It is an arithmetic number, because the mean of its divisors is an integer number (6954256387).

Almost surely, 2^20862624721 is an apocalyptic number.

20862624721 is the 144439-th square number.

20862624721 is the 72220-th centered octagonal number.

It is an amenable number.

20862624721 is a deficient number, since it is larger than the sum of its proper divisors (144440).

20862624721 is an frugal number, since it uses more digits than its factorization.

20862624721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288878 (or 144439 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 40.

The spelling of 20862624721 in words is "twenty billion, eight hundred sixty-two million, six hundred twenty-four thousand, seven hundred twenty-one".