215071720 has 16 divisors (see below), whose sum is σ = 483911460. Its totient is φ = 86028672.

The previous prime is 215071711. The next prime is 215071741. The reversal of 215071720 is 27170512.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 214153956 + 917764 = 14634^2 + 958^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2688357 + ... + 2688436.

Almost surely, 2^215071720 is an apocalyptic number.

215071720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215071720 is an abundant number, since it is smaller than the sum of its proper divisors (268839740).

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

215071720 is a wasteful number, since it uses less digits than its factorization.

215071720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5376804 (or 5376800 counting only the distinct ones).

The product of its (nonzero) digits is 980, while the sum is 25.

The square root of 215071720 is about 14665.3237263962. The cubic root of 215071720 is about 599.1392472465.

The spelling of 215071720 in words is "two hundred fifteen million, seventy-one thousand, seven hundred twenty".