25491321600 has 108 divisors (see below), whose sum is σ = 84126735336. Its totient is φ = 6797680640.

The previous prime is 25491321599. The next prime is 25491321637. The reversal of 25491321600 is 612319452.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 644637 + ... + 683036.

Almost surely, 2^25491321600 is an apocalyptic number.

25491321600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25491321600 is an abundant number, since it is smaller than the sum of its proper divisors (58635413736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25491321600 is a wasteful number, since it uses less digits than its factorization.

25491321600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1327702 (or 1327683 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The spelling of 25491321600 in words is "twenty-five billion, four hundred ninety-one million, three hundred twenty-one thousand, six hundred".