1491964591 has 32 divisors (see below), whose sum is σ = 1735776000. Its totient is φ = 1270162944.

The previous prime is 1491964571. The next prime is 1491964619. The reversal of 1491964591 is 1954691941.

It is not a de Polignac number, because 1491964591 - 2⁹ = 1491964079 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1491964571) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2989660 + ... + 2990158.

It is an arithmetic number, because the mean of its divisors is an integer number (54243000).

Almost surely, 2^1491964591 is an apocalyptic number.

1491964591 is a deficient number, since it is larger than the sum of its proper divisors (243811409).

1491964591 is a wasteful number, since it uses less digits than its factorization.

1491964591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 775.

The product of its digits is 349920, while the sum is 49.

The square root of 1491964591 is about 38625.9574768057. The cubic root of 1491964591 is about 1142.6665267753. Note that the first 3 decimals are identical.

The spelling of 1491964591 in words is "one billion, four hundred ninety-one million, nine hundred sixty-four thousand, five hundred ninety-one".