1639428027 has 4 divisors (see below), whose sum is σ = 2185904040. Its totient is φ = 1092952016.

The previous prime is 1639427981. The next prime is 1639428041. The reversal of 1639428027 is 7208249361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7208249361 = 3 ⋅2402749787.

It is a cyclic number.

It is not a de Polignac number, because 1639428027 - 2⁸ = 1639427771 is a prime.

It is a super-2 number, since 2×1639428027² = 5375448511426225458, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1639428027.

It is not an unprimeable number, because it can be changed into a prime (1639428097) 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, 273238002 + ... + 273238007.

It is an arithmetic number, because the mean of its divisors is an integer number (546476010).

Almost surely, 2^1639428027 is an apocalyptic number.

1639428027 is a deficient number, since it is larger than the sum of its proper divisors (546476013).

1639428027 is an equidigital number, since it uses as much as digits as its factorization.

1639428027 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546476012.

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 1639428027 is about 40489.8509135314. The cubic root of 1639428027 is about 1179.1365959715.

The spelling of 1639428027 in words is "one billion, six hundred thirty-nine million, four hundred twenty-eight thousand, twenty-seven".