25816949 has 4 divisors (see below), whose sum is σ = 26180640. Its totient is φ = 25453260.

The previous prime is 25816927. The next prime is 25816951. The reversal of 25816949 is 94961852.

25816949 = T₃₈₂ + T₃₈₃ + ... + T₅₉₄.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25816949 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25816919) 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, 181739 + ... + 181880.

It is an arithmetic number, because the mean of its divisors is an integer number (6545160).

Almost surely, 2^25816949 is an apocalyptic number.

It is an amenable number.

25816949 is a deficient number, since it is larger than the sum of its proper divisors (363691).

25816949 is an equidigital number, since it uses as much as digits as its factorization.

25816949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363690.

The product of its digits is 155520, while the sum is 44.

The square root of 25816949 is about 5081.0381813169. The cubic root of 25816949 is about 295.5527279761.

The spelling of 25816949 in words is "twenty-five million, eight hundred sixteen thousand, nine hundred forty-nine".