1403646661 has 12 divisors (see below), whose sum is σ = 1477602724. Its totient is φ = 1332979200.

The previous prime is 1403646637. The next prime is 1403646677. The reversal of 1403646661 is 1666463041.

It can be written as a sum of positive squares in 6 ways, for example, as 69205761 + 1334440900 = 8319^2 + 36530^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1403646661 is a prime.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1403646661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1403046661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37621 + ... + 64981.

Almost surely, 2^1403646661 is an apocalyptic number.

It is an amenable number.

1403646661 is a deficient number, since it is larger than the sum of its proper divisors (73956063).

1403646661 is an equidigital number, since it uses as much as digits as its factorization.

1403646661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27480 (or 27451 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 37.

The square root of 1403646661 is about 37465.2727335595. The cubic root of 1403646661 is about 1119.6594045658.

The spelling of 1403646661 in words is "one billion, four hundred three million, six hundred forty-six thousand, six hundred sixty-one".