20694661291 has 2 divisors, whose sum is σ = 20694661292. Its totient is φ = 20694661290.

The previous prime is 20694661279. The next prime is 20694661301. The reversal of 20694661291 is 19216649602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20694661291 - 2¹⁵ = 20694628523 is a prime.

It is not a weakly prime, because it can be changed into another prime (20694661591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10347330645 + 10347330646.

It is an arithmetic number, because the mean of its divisors is an integer number (10347330646).

Almost surely, 2^20694661291 is an apocalyptic number.

20694661291 is a deficient number, since it is larger than the sum of its proper divisors (1).

20694661291 is an equidigital number, since it uses as much as digits as its factorization.

20694661291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 46.

The spelling of 20694661291 in words is "twenty billion, six hundred ninety-four million, six hundred sixty-one thousand, two hundred ninety-one".