1638044085 has 8 divisors (see below), whose sum is σ = 2620870560. Its totient is φ = 873623504.

The previous prime is 1638044071. The next prime is 1638044087. The reversal of 1638044085 is 5804408361.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1638044085 - 2⁸ = 1638043829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638044087) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54601455 + ... + 54601484.

It is an arithmetic number, because the mean of its divisors is an integer number (327608820).

Almost surely, 2^1638044085 is an apocalyptic number.

1638044085 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1638044085 is a deficient number, since it is larger than the sum of its proper divisors (982826475).

1638044085 is a wasteful number, since it uses less digits than its factorization.

1638044085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109202947.

The product of its (nonzero) digits is 92160, while the sum is 39.

The square root of 1638044085 is about 40472.7573189670. The cubic root of 1638044085 is about 1178.8047086647.

The spelling of 1638044085 in words is "one billion, six hundred thirty-eight million, forty-four thousand, eighty-five".