25709020991 has 2 divisors, whose sum is σ = 25709020992. Its totient is φ = 25709020990.

The previous prime is 25709020979. The next prime is 25709021017. The reversal of 25709020991 is 19902090752.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25709020991 - 2¹⁰ = 25709019967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25709020691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12854510495 + 12854510496.

It is an arithmetic number, because the mean of its divisors is an integer number (12854510496).

Almost surely, 2^25709020991 is an apocalyptic number.

25709020991 is a deficient number, since it is larger than the sum of its proper divisors (1).

25709020991 is an equidigital number, since it uses as much as digits as its factorization.

25709020991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 102060, while the sum is 44.

The spelling of 25709020991 in words is "twenty-five billion, seven hundred nine million, twenty thousand, nine hundred ninety-one".