20001651 has 16 divisors (see below), whose sum is σ = 27972864. Its totient is φ = 12688544.

The previous prime is 20001613. The next prime is 20001659. The reversal of 20001651 is 15610002.

It is a cyclic number.

It is not a de Polignac number, because 20001651 - 2⁹ = 20001139 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20001651.

It is not an unprimeable number, because it can be changed into a prime (20001659) 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 15 ways as a sum of consecutive naturals, for example, 15025 + ... + 16301.

It is an arithmetic number, because the mean of its divisors is an integer number (1748304).

Almost surely, 2^20001651 is an apocalyptic number.

20001651 is a deficient number, since it is larger than the sum of its proper divisors (7971213).

20001651 is a wasteful number, since it uses less digits than its factorization.

20001651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1530.

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 20001651 is about 4472.3205386019. The cubic root of 20001651 is about 271.4492306264.

Adding to 20001651 its reverse (15610002), we get a palindrome (35611653).

The spelling of 20001651 in words is "twenty million, one thousand, six hundred fifty-one".