2166679780 has 12 divisors (see below), whose sum is σ = 4550027580. Its totient is φ = 866671904.

The previous prime is 2166679777. The next prime is 2166679783. The reversal of 2166679780 is 879766612.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (2166679777) and next prime (2166679783).

It can be written as a sum of positive squares in 2 ways, for example, as 1196606464 + 970073316 = 34592^2 + 31146^2 .

It is not an unprimeable number, because it can be changed into a prime (2166679783) 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, 54166975 + ... + 54167014.

It is an arithmetic number, because the mean of its divisors is an integer number (379168965).

Almost surely, 2^2166679780 is an apocalyptic number.

2166679780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2166679780 is an abundant number, since it is smaller than the sum of its proper divisors (2383347800).

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

2166679780 is a wasteful number, since it uses less digits than its factorization.

2166679780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108333998 (or 108333996 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 52.

The square root of 2166679780 is about 46547.6076721457. The cubic root of 2166679780 is about 1293.9919566447.

The spelling of 2166679780 in words is "two billion, one hundred sixty-six million, six hundred seventy-nine thousand, seven hundred eighty".