20125538 has 4 divisors (see below), whose sum is σ = 30188310. Its totient is φ = 10062768.

The previous prime is 20125537. The next prime is 20125543. The reversal of 20125538 is 83552102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83552102 = 2 ⋅41776051.

It can be written as a sum of positive squares in only one way, i.e., 13890529 + 6235009 = 3727^2 + 2497^2 .

It is not an unprimeable number, because it can be changed into a prime (20125537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5031383 + ... + 5031386.

Almost surely, 2^20125538 is an apocalyptic number.

20125538 is a deficient number, since it is larger than the sum of its proper divisors (10062772).

20125538 is a wasteful number, since it uses less digits than its factorization.

20125538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10062771.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 20125538 is about 4486.1495739665. The cubic root of 20125538 is about 272.0085150881.

The spelling of 20125538 in words is "twenty million, one hundred twenty-five thousand, five hundred thirty-eight".