1356638643 has 12 divisors (see below), whose sum is σ = 1986433800. Its totient is φ = 892035936.

The previous prime is 1356638629. The next prime is 1356638651. The reversal of 1356638643 is 3468366531.

1356638643 is a `hidden beast` number, since 1 + 3 + 5 + 6 + 638 + 6 + 4 + 3 = 666.

1356638643 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1356638643 - 2¹⁰ = 1356637619 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1356638653) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1031793 + ... + 1033106.

It is an arithmetic number, because the mean of its divisors is an integer number (165536150).

Almost surely, 2^1356638643 is an apocalyptic number.

1356638643 is a deficient number, since it is larger than the sum of its proper divisors (629795157).

1356638643 is a wasteful number, since it uses less digits than its factorization.

1356638643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2064978 (or 2064975 counting only the distinct ones).

The product of its digits is 933120, while the sum is 45.

The square root of 1356638643 is about 36832.5758398731. The cubic root of 1356638643 is about 1107.0181155125.

The spelling of 1356638643 in words is "one billion, three hundred fifty-six million, six hundred thirty-eight thousand, six hundred forty-three".