1642765643 has 4 divisors (see below), whose sum is σ = 1658714928. Its totient is φ = 1626816360.

The previous prime is 1642765603. The next prime is 1642765661. The reversal of 1642765643 is 3465672461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3465672461 = 1231 ⋅2815331.

It is a cyclic number.

It is not a de Polignac number, because 1642765643 - 2⁸ = 1642765387 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1642765594 and 1642765603.

It is not an unprimeable number, because it can be changed into a prime (1642765603) 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 3 ways as a sum of consecutive naturals, for example, 7974488 + ... + 7974693.

It is an arithmetic number, because the mean of its divisors is an integer number (414678732).

Almost surely, 2^1642765643 is an apocalyptic number.

1642765643 is a deficient number, since it is larger than the sum of its proper divisors (15949285).

1642765643 is a wasteful number, since it uses less digits than its factorization.

1642765643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15949284.

The product of its digits is 725760, while the sum is 44.

The square root of 1642765643 is about 40531.0454219972. The cubic root of 1642765643 is about 1179.9362320706.

The spelling of 1642765643 in words is "one billion, six hundred forty-two million, seven hundred sixty-five thousand, six hundred forty-three".