9139981820 has 24 divisors (see below), whose sum is σ = 19196119824. Its totient is φ = 3655581696.

The previous prime is 9139981817. The next prime is 9139981871. The reversal of 9139981820 is 281899319.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 208892 + ... + 248828.

It is an arithmetic number, because the mean of its divisors is an integer number (799838326).

Almost surely, 2^9139981820 is an apocalyptic number.

It is an amenable number.

9139981820 is an abundant number, since it is smaller than the sum of its proper divisors (10056138004).

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

9139981820 is a wasteful number, since it uses less digits than its factorization.

9139981820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51389 (or 51387 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 50.

The square root of 9139981820 is about 95603.2521413367. The cubic root of 9139981820 is about 2090.8126095379.

The spelling of 9139981820 in words is "nine billion, one hundred thirty-nine million, nine hundred eighty-one thousand, eight hundred twenty".