1601994239 has 4 divisors (see below), whose sum is σ = 1608641760. Its totient is φ = 1595346720.

The previous prime is 1601994227. The next prime is 1601994281. The reversal of 1601994239 is 9324991061.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1601994239 - 2⁸ = 1601993983 is a prime.

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 1601994239.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601994209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3323399 + ... + 3323880.

It is an arithmetic number, because the mean of its divisors is an integer number (402160440).

Almost surely, 2^1601994239 is an apocalyptic number.

1601994239 is a deficient number, since it is larger than the sum of its proper divisors (6647521).

1601994239 is an equidigital number, since it uses as much as digits as its factorization.

1601994239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6647520.

The product of its (nonzero) digits is 104976, while the sum is 44.

The square root of 1601994239 is about 40024.9202247800. The cubic root of 1601994239 is about 1170.0928260537.

The spelling of 1601994239 in words is "one billion, six hundred one million, nine hundred ninety-four thousand, two hundred thirty-nine".