2001656603 has 2 divisors, whose sum is σ = 2001656604. Its totient is φ = 2001656602.

The previous prime is 2001656567. The next prime is 2001656611. The reversal of 2001656603 is 3066561002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2001656603 - 2¹⁴ = 2001640219 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001656663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000828301 + 1000828302.

It is an arithmetic number, because the mean of its divisors is an integer number (1000828302).

Almost surely, 2^2001656603 is an apocalyptic number.

2001656603 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001656603 is an equidigital number, since it uses as much as digits as its factorization.

2001656603 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 2001656603 is about 44739.8771008594. The cubic root of 2001656603 is about 1260.2688187252.

The spelling of 2001656603 in words is "two billion, one million, six hundred fifty-six thousand, six hundred three".