1639920 has 40 divisors (see below), whose sum is σ = 5084496. Its totient is φ = 437248.

The previous prime is 1639919. The next prime is 1639927. The reversal of 1639920 is 299361.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1639927) 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, 3177 + ... + 3656.

2^1639920 is an apocalyptic number.

1639920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1639920 is an abundant number, since it is smaller than the sum of its proper divisors (3444576).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1639920 is a wasteful number, since it uses less digits than its factorization.

1639920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6849 (or 6843 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 30.

The square root of 1639920 is about 1280.5936123533. The cubic root of 1639920 is about 117.9254532500.

The spelling of 1639920 in words is "one million, six hundred thirty-nine thousand, nine hundred twenty".