20280323281 has 9 divisors (see below), whose sum is σ = 21546029649. Its totient is φ = 19085084544.

The previous prime is 20280323269. The next prime is 20280323317. The reversal of 20280323281 is 18232308202.

The square root of 20280323281 is 142409.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 207100881 + 20073222400 = 14391^2 + 141680^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20280323281 is a prime.

It is a super-2 number, since 2×20280323281² (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 (20280323201) 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 8 ways as a sum of consecutive naturals, for example, 2416765 + ... + 2425141.

Almost surely, 2^20280323281 is an apocalyptic number.

20280323281 is the 142409-th square number.

20280323281 is the 71205-th centered octagonal number.

It is an amenable number.

20280323281 is a deficient number, since it is larger than the sum of its proper divisors (1265706368).

20280323281 is an frugal number, since it uses more digits than its factorization.

20280323281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16788 (or 8394 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 31.

Multiplying 20280323281 by its product of nonzero digits (9216), we get a square (186903459357696 = 13671264²).

The spelling of 20280323281 in words is "twenty billion, two hundred eighty million, three hundred twenty-three thousand, two hundred eighty-one".