20725557 has 8 divisors (see below), whose sum is σ = 27902784. Its totient is φ = 13682688.

The previous prime is 20725547. The next prime is 20725589. The reversal of 20725557 is 75552702.

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

It is not a de Polignac number, because 20725557 - 2⁶ = 20725493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20725547) 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, 33228 + ... + 33845.

It is an arithmetic number, because the mean of its divisors is an integer number (3487848).

Almost surely, 2^20725557 is an apocalyptic number.

It is an amenable number.

20725557 is a deficient number, since it is larger than the sum of its proper divisors (7177227).

20725557 is a wasteful number, since it uses less digits than its factorization.

20725557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67179.

The product of its (nonzero) digits is 24500, while the sum is 33.

The square root of 20725557 is about 4552.5330311817. The cubic root of 20725557 is about 274.6852906735.

The spelling of 20725557 in words is "twenty million, seven hundred twenty-five thousand, five hundred fifty-seven".