20201651 has 2 divisors, whose sum is σ = 20201652. Its totient is φ = 20201650.

The previous prime is 20201563. The next prime is 20201653. The reversal of 20201651 is 15610202.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20201651 is a prime.

It is a Sophie Germain prime.

Together with 20201653, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20201653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10100825 + 10100826.

It is an arithmetic number, because the mean of its divisors is an integer number (10100826).

Almost surely, 2^20201651 is an apocalyptic number.

20201651 is a deficient number, since it is larger than the sum of its proper divisors (1).

20201651 is an equidigital number, since it uses as much as digits as its factorization.

20201651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 20201651 is about 4494.6246784353. The cubic root of 20201651 is about 272.3509877440.

Adding to 20201651 its reverse (15610202), we get a palindrome (35811853).

The spelling of 20201651 in words is "twenty million, two hundred one thousand, six hundred fifty-one".