20725251 has 8 divisors (see below), whose sum is σ = 27742224. Its totient is φ = 13762560.

The previous prime is 20725249. The next prime is 20725273. The reversal of 20725251 is 15252702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20725251 - 2¹ = 20725249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20725241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12670 + ... + 14211.

It is an arithmetic number, because the mean of its divisors is an integer number (3467778).

Almost surely, 2^20725251 is an apocalyptic number.

20725251 is a deficient number, since it is larger than the sum of its proper divisors (7016973).

20725251 is a wasteful number, since it uses less digits than its factorization.

20725251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27141.

The product of its (nonzero) digits is 1400, while the sum is 24.

The square root of 20725251 is about 4552.4994233937. The cubic root of 20725251 is about 274.6839388142.

Adding to 20725251 its reverse (15252702), we get a palindrome (35977953).

The spelling of 20725251 in words is "twenty million, seven hundred twenty-five thousand, two hundred fifty-one".