2179664540 has 12 divisors (see below), whose sum is σ = 4577295576. Its totient is φ = 871865808.

The previous prime is 2179664521. The next prime is 2179664549. The reversal of 2179664540 is 454669712.

It is a junction number, because it is equal to n+sod(n) for n = 2179664491 and 2179664500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2179664549) 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, 54491594 + ... + 54491633.

It is an arithmetic number, because the mean of its divisors is an integer number (381441298).

Almost surely, 2^2179664540 is an apocalyptic number.

2179664540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2179664540 is an abundant number, since it is smaller than the sum of its proper divisors (2397631036).

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

2179664540 is a wasteful number, since it uses less digits than its factorization.

2179664540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108983236 (or 108983234 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 44.

The square root of 2179664540 is about 46686.8775995997. The cubic root of 2179664540 is about 1296.5717443468.

The spelling of 2179664540 in words is "two billion, one hundred seventy-nine million, six hundred sixty-four thousand, five hundred forty".