20031620281 has 2 divisors, whose sum is σ = 20031620282. Its totient is φ = 20031620280.

The previous prime is 20031620243. The next prime is 20031620317. The reversal of 20031620281 is 18202613002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18764616256 + 1267004025 = 136984^2 + 35595^2 .

It is a cyclic number.

It is not a de Polignac number, because 20031620281 - 2²³ = 20023231673 is a prime.

It is a super-2 number, since 2×20031620281² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20031623281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10015810140 + 10015810141.

It is an arithmetic number, because the mean of its divisors is an integer number (10015810141).

Almost surely, 2^20031620281 is an apocalyptic number.

It is an amenable number.

20031620281 is a deficient number, since it is larger than the sum of its proper divisors (1).

20031620281 is an equidigital number, since it uses as much as digits as its factorization.

20031620281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 25.

The spelling of 20031620281 in words is "twenty billion, thirty-one million, six hundred twenty thousand, two hundred eighty-one".