1638986076 has 120 divisors (see below), whose sum is σ = 5273489760. Its totient is φ = 432252288.

The previous prime is 1638986059. The next prime is 1638986101. The reversal of 1638986076 is 6706898361.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1690 + ... + 57278.

It is an arithmetic number, because the mean of its divisors is an integer number (43945748).

Almost surely, 2^1638986076 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1638986076, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2636744880).

1638986076 is an abundant number, since it is smaller than the sum of its proper divisors (3634503684).

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

1638986076 is a wasteful number, since it uses less digits than its factorization.

1638986076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55625 (or 55614 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The square root of 1638986076 is about 40484.3929928559. The cubic root of 1638986076 is about 1179.0306306748.

The spelling of 1638986076 in words is "one billion, six hundred thirty-eight million, nine hundred eighty-six thousand, seventy-six".