20125840 has 80 divisors (see below), whose sum is σ = 54246528. Its totient is φ = 6801408.

The previous prime is 20125829. The next prime is 20125843. The reversal of 20125840 is 4852102.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (20125843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46264 + ... + 46696.

Almost surely, 2^20125840 is an apocalyptic number.

20125840 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 20125840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27123264).

20125840 is an abundant number, since it is smaller than the sum of its proper divisors (34120688).

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

20125840 is a wasteful number, since it uses less digits than its factorization.

20125840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536 (or 530 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 20125840 is about 4486.1832329944. The cubic root of 20125840 is about 272.0098756507.

Adding to 20125840 its reverse (4852102), we get a palindrome (24977942).

The spelling of 20125840 in words is "twenty million, one hundred twenty-five thousand, eight hundred forty".