25121920 has 64 divisors (see below), whose sum is σ = 63617400. Its totient is φ = 9453568.

The previous prime is 25121897. The next prime is 25121939. The reversal of 25121920 is 2912152.

It can be written as a sum of positive squares in 4 ways, for example, as 24681024 + 440896 = 4968^2 + 664^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×25121920² = 1262221728972800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 25121891 and 25121900.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9726 + ... + 12034.

Almost surely, 2^25121920 is an apocalyptic number.

25121920 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 25121920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31808700).

25121920 is an abundant number, since it is smaller than the sum of its proper divisors (38495480).

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

25121920 is a wasteful number, since it uses less digits than its factorization.

25121920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2345 (or 2333 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 25121920 is about 5012.1771716491. The cubic root of 25121920 is about 292.8763315378.

The spelling of 25121920 in words is "twenty-five million, one hundred twenty-one thousand, nine hundred twenty".