20722601 has 4 divisors (see below), whose sum is σ = 21391104. Its totient is φ = 20054100.

The previous prime is 20722591. The next prime is 20722619. The reversal of 20722601 is 10622702.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10622702 = 2 ⋅5311351.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20722601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20722621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334205 + ... + 334266.

It is an arithmetic number, because the mean of its divisors is an integer number (5347776).

Almost surely, 2^20722601 is an apocalyptic number.

It is an amenable number.

20722601 is a deficient number, since it is larger than the sum of its proper divisors (668503).

20722601 is an equidigital number, since it uses as much as digits as its factorization.

20722601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668502.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 20722601 is about 4552.2083651784. The cubic root of 20722601 is about 274.6722309791.

The spelling of 20722601 in words is "twenty million, seven hundred twenty-two thousand, six hundred one".