25205212897 has 4 divisors (see below), whose sum is σ = 25550489860. Its totient is φ = 24859935936.

The previous prime is 25205212891. The next prime is 25205212909. The reversal of 25205212897 is 79821250252.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6195421521 + 19009791376 = 78711^2 + 137876^2 .

It is a cyclic number.

It is not a de Polignac number, because 25205212897 - 2³ = 25205212889 is a prime.

It is a super-4 number, since 4×25205212897⁴ (a number of 43 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25205212891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172638372 + ... + 172638517.

It is an arithmetic number, because the mean of its divisors is an integer number (6387622465).

Almost surely, 2^25205212897 is an apocalyptic number.

It is an amenable number.

25205212897 is a deficient number, since it is larger than the sum of its proper divisors (345276963).

25205212897 is an equidigital number, since it uses as much as digits as its factorization.

25205212897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345276962.

The product of its (nonzero) digits is 201600, while the sum is 43.

The spelling of 25205212897 in words is "twenty-five billion, two hundred five million, two hundred twelve thousand, eight hundred ninety-seven".