2171778480 has 160 divisors (see below), whose sum is σ = 7573533120. Its totient is φ = 579094272.

The previous prime is 2171778467. The next prime is 2171778523. The reversal of 2171778480 is 848771712.

It is a super-2 number, since 2×2171778480² = 9433243532382220800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 168754 + ... + 181166.

It is an arithmetic number, because the mean of its divisors is an integer number (47334582).

Almost surely, 2^2171778480 is an apocalyptic number.

2171778480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2171778480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3786766560).

2171778480 is an abundant number, since it is smaller than the sum of its proper divisors (5401754640).

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

2171778480 is an equidigital number, since it uses as much as digits as its factorization.

2171778480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12447 (or 12423 counting only the distinct ones).

The product of its (nonzero) digits is 175616, while the sum is 45.

The square root of 2171778480 is about 46602.3441470491. The cubic root of 2171778480 is about 1295.0061825458.

The spelling of 2171778480 in words is "two billion, one hundred seventy-one million, seven hundred seventy-eight thousand, four hundred eighty".