20651081 has 8 divisors (see below), whose sum is σ = 23714400. Its totient is φ = 17785440.

The previous prime is 20651077. The next prime is 20651087. The reversal of 20651081 is 18015602.

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 20651081 - 2² = 20651077 is a prime.

It is a super-2 number, since 2×20651081² = 852934292937122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20651087) 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, 49196 + ... + 49613.

It is an arithmetic number, because the mean of its divisors is an integer number (2964300).

Almost surely, 2^20651081 is an apocalyptic number.

It is an amenable number.

20651081 is a deficient number, since it is larger than the sum of its proper divisors (3063319).

20651081 is a wasteful number, since it uses less digits than its factorization.

20651081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98839.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 20651081 is about 4544.3460475628. The cubic root of 20651081 is about 274.3558742763.

Adding to 20651081 its reverse (18015602), we get a palindrome (38666683).

The spelling of 20651081 in words is "twenty million, six hundred fifty-one thousand, eighty-one".