2156673840 has 80 divisors (see below), whose sum is σ = 6692571648. Its totient is φ = 574521088.

The previous prime is 2156673811. The next prime is 2156673859. The reversal of 2156673840 is 483766512.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 2156673792 and 2156673801.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 260647 + ... + 268793.

Almost surely, 2^2156673840 is an apocalyptic number.

2156673840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2156673840 is an abundant number, since it is smaller than the sum of its proper divisors (4535897808).

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

2156673840 is a wasteful number, since it uses less digits than its factorization.

2156673840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9266 (or 9260 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 42.

The square root of 2156673840 is about 46440.0025839793. The cubic root of 2156673840 is about 1291.9969551379.

The spelling of 2156673840 in words is "two billion, one hundred fifty-six million, six hundred seventy-three thousand, eight hundred forty".