20722505 has 8 divisors (see below), whose sum is σ = 25087752. Its totient is φ = 16430848.

The previous prime is 20722453. The next prime is 20722519. The reversal of 20722505 is 50522702.

It can be written as a sum of positive squares in 4 ways, for example, as 1990921 + 18731584 = 1411^2 + 4328^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20722505 - 2¹⁴ = 20706121 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17774 + ... + 18903.

It is an arithmetic number, because the mean of its divisors is an integer number (3135969).

Almost surely, 2^20722505 is an apocalyptic number.

It is an amenable number.

20722505 is a deficient number, since it is larger than the sum of its proper divisors (4365247).

20722505 is a wasteful number, since it uses less digits than its factorization.

20722505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36795.

The product of its (nonzero) digits is 1400, while the sum is 23.

The square root of 20722505 is about 4552.1978208334. The cubic root of 20722505 is about 274.6718068274.

The spelling of 20722505 in words is "twenty million, seven hundred twenty-two thousand, five hundred five".