28207136693 has 2 divisors, whose sum is σ = 28207136694. Its totient is φ = 28207136692.

The previous prime is 28207136567. The next prime is 28207136719. The reversal of 28207136693 is 39663170282.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24810345169 + 3396791524 = 157513^2 + 58282^2 .

It is a cyclic number.

It is not a de Polignac number, because 28207136693 - 2²² = 28202942389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28207136393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14103568346 + 14103568347.

It is an arithmetic number, because the mean of its divisors is an integer number (14103568347).

Almost surely, 2^28207136693 is an apocalyptic number.

It is an amenable number.

28207136693 is a deficient number, since it is larger than the sum of its proper divisors (1).

28207136693 is an equidigital number, since it uses as much as digits as its factorization.

28207136693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 653184, while the sum is 47.

The spelling of 28207136693 in words is "twenty-eight billion, two hundred seven million, one hundred thirty-six thousand, six hundred ninety-three".