25491000 has 128 divisors (see below), whose sum is σ = 82555200. Its totient is φ = 6540800.

The previous prime is 25490999. The next prime is 25491001. The reversal of 25491000 is 19452.

It is an interprime number because it is at equal distance from previous prime (25490999) and next prime (25491001).

It is a super-3 number, since 3×25491000³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25491001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 86854 + ... + 87146.

Almost surely, 2^25491000 is an apocalyptic number.

25491000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25491000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41277600).

25491000 is an abundant number, since it is smaller than the sum of its proper divisors (57064200).

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

25491000 is a wasteful number, since it uses less digits than its factorization.

25491000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346 (or 332 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 25491000 is about 5048.8612577491. The cubic root of 25491000 is about 294.3036337382.

The spelling of 25491000 in words is "twenty-five million, four hundred ninety-one thousand".