25909920 has 144 divisors (see below), whose sum is σ = 93169440. Its totient is φ = 6538752.

The previous prime is 25909913. The next prime is 25909957. The reversal of 25909920 is 2990952.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26887 + ... + 27833.

It is an arithmetic number, because the mean of its divisors is an integer number (647010).

Almost surely, 2^25909920 is an apocalyptic number.

25909920 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 25909920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46584720).

25909920 is an abundant number, since it is smaller than the sum of its proper divisors (67259520).

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

25909920 is a wasteful number, since it uses less digits than its factorization.

25909920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 987 (or 976 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 36.

The square root of 25909920 is about 5090.1787787857. The cubic root of 25909920 is about 295.9070806466.

The spelling of 25909920 in words is "twenty-five million, nine hundred nine thousand, nine hundred twenty".