20679971 has 8 divisors (see below), whose sum is σ = 22331904. Its totient is φ = 19036800.

The previous prime is 20679959. The next prime is 20679977. The reversal of 20679971 is 17997602.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20679971 is a prime.

It is a super-2 number, since 2×20679971² = 855322401121682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20679977) 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 7 ways as a sum of consecutive naturals, for example, 3230 + ... + 7196.

It is an arithmetic number, because the mean of its divisors is an integer number (2791488).

Almost surely, 2^20679971 is an apocalyptic number.

20679971 is a deficient number, since it is larger than the sum of its proper divisors (1651933).

20679971 is a wasteful number, since it uses less digits than its factorization.

20679971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4381.

The product of its (nonzero) digits is 47628, while the sum is 41.

The square root of 20679971 is about 4547.5236118134. The cubic root of 20679971 is about 274.4837521336.

The spelling of 20679971 in words is "twenty million, six hundred seventy-nine thousand, nine hundred seventy-one".