4000651 has 2 divisors, whose sum is σ = 4000652. Its totient is φ = 4000650.

The previous prime is 4000649. The next prime is 4000669. The reversal of 4000651 is 1560004.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 4000651 - 2¹ = 4000649 is a prime.

Together with 4000649, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (4000631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2000325 + 2000326.

It is an arithmetic number, because the mean of its divisors is an integer number (2000326).

Almost surely, 2^4000651 is an apocalyptic number.

4000651 is the 895-th centered decagonal number.

4000651 is a deficient number, since it is larger than the sum of its proper divisors (1).

4000651 is an equidigital number, since it uses as much as digits as its factorization.

4000651 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 16.

The square root of 4000651 is about 2000.1627433786. The cubic root of 4000651 is about 158.7487163804.

Adding to 4000651 its reverse (1560004), we get a palindrome (5560655).

The spelling of 4000651 in words is "four million, six hundred fifty-one", and thus it is an aban number.