20725147 has 4 divisors (see below), whose sum is σ = 20740216. Its totient is φ = 20710080.

The previous prime is 20725129. The next prime is 20725153. The reversal of 20725147 is 74152702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20725147 - 2¹⁵ = 20692379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20725127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5238 + ... + 8299.

It is an arithmetic number, because the mean of its divisors is an integer number (5185054).

Almost surely, 2^20725147 is an apocalyptic number.

20725147 is a deficient number, since it is larger than the sum of its proper divisors (15069).

20725147 is a wasteful number, since it uses less digits than its factorization.

20725147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15068.

The product of its (nonzero) digits is 3920, while the sum is 28.

The square root of 20725147 is about 4552.4880010825. The cubic root of 20725147 is about 274.6834793557.

Adding to 20725147 its reverse (74152702), we get a palindrome (94877849).

The spelling of 20725147 in words is "twenty million, seven hundred twenty-five thousand, one hundred forty-seven".