20280007997 has 2 divisors, whose sum is σ = 20280007998. Its totient is φ = 20280007996.

The previous prime is 20280007987. The next prime is 20280008011. The reversal of 20280007997 is 79970008202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14321866276 + 5958141721 = 119674^2 + 77189^2 .

It is a cyclic number.

It is not a de Polignac number, because 20280007997 - 2²⁸ = 20011572541 is a prime.

It is a super-2 number, since 2×20280007997² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20280007987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10140003998 + 10140003999.

It is an arithmetic number, because the mean of its divisors is an integer number (10140003999).

Almost surely, 2^20280007997 is an apocalyptic number.

It is an amenable number.

20280007997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20280007997 is an equidigital number, since it uses as much as digits as its factorization.

20280007997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127008, while the sum is 44.

The spelling of 20280007997 in words is "twenty billion, two hundred eighty million, seven thousand, nine hundred ninety-seven".