20881617 has 8 divisors (see below), whose sum is σ = 28489824. Its totient is φ = 13597248.

The previous prime is 20881613. The next prime is 20881633. The reversal of 20881617 is 71618802.

It is a happy number.

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

It is not a de Polignac number, because 20881617 - 2² = 20881613 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20881613) 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, 80808 + ... + 81065.

It is an arithmetic number, because the mean of its divisors is an integer number (3561228).

Almost surely, 2^20881617 is an apocalyptic number.

It is an amenable number.

20881617 is a deficient number, since it is larger than the sum of its proper divisors (7608207).

20881617 is a wasteful number, since it uses less digits than its factorization.

20881617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161919.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 20881617 is about 4569.6407955112. The cubic root of 20881617 is about 275.3730122716.

The spelling of 20881617 in words is "twenty million, eight hundred eighty-one thousand, six hundred seventeen".