20616997 has 8 divisors (see below), whose sum is σ = 20849600. Its totient is φ = 20386080.

The previous prime is 20616991. The next prime is 20617007. The reversal of 20616997 is 79961602.

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 20616997 - 2³ = 20616989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20616991) 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, 62122 + ... + 62452.

It is an arithmetic number, because the mean of its divisors is an integer number (2606200).

Almost surely, 2^20616997 is an apocalyptic number.

It is an amenable number.

20616997 is a deficient number, since it is larger than the sum of its proper divisors (232603).

20616997 is a wasteful number, since it uses less digits than its factorization.

20616997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 843.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 20616997 is about 4540.5943443563. The cubic root of 20616997 is about 274.2048524010.

The spelling of 20616997 in words is "twenty million, six hundred sixteen thousand, nine hundred ninety-seven".