25499899451 has 24 divisors (see below), whose sum is σ = 28072074096. Its totient is φ = 23149701120.

The previous prime is 25499899409. The next prime is 25499899459. The reversal of 25499899451 is 15499899452.

It is not a de Polignac number, because 25499899451 - 2⁶ = 25499899387 is a prime.

It is a super-2 number, since 2×25499899451² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25499899459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2496611 + ... + 2506803.

It is an arithmetic number, because the mean of its divisors is an integer number (1169669754).

Almost surely, 2^25499899451 is an apocalyptic number.

25499899451 is a deficient number, since it is larger than the sum of its proper divisors (2572174645).

25499899451 is a wasteful number, since it uses less digits than its factorization.

25499899451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10463 (or 10450 counting only the distinct ones).

The product of its digits is 41990400, while the sum is 65.

Subtracting from 25499899451 its reverse (15499899452), we obtain a palindrome (9999999999).

The spelling of 25499899451 in words is "twenty-five billion, four hundred ninety-nine million, eight hundred ninety-nine thousand, four hundred fifty-one".