215280020 has 24 divisors (see below), whose sum is σ = 452445000. Its totient is φ = 86044032.

The previous prime is 215279969. The next prime is 215280047. The reversal of 215280020 is 20082512.

215280020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 40934404 + 174345616 = 6398^2 + 13204^2 .

It is a super-2 number, since 2×215280020² = 92690974022400800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 215279974 and 215280001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27506 + ... + 34454.

It is an arithmetic number, because the mean of its divisors is an integer number (18851875).

Almost surely, 2^215280020 is an apocalyptic number.

215280020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215280020 is an abundant number, since it is smaller than the sum of its proper divisors (237164980).

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

215280020 is a wasteful number, since it uses less digits than its factorization.

215280020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8507 (or 8505 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 215280020 is about 14672.4237943156. The cubic root of 215280020 is about 599.3326097776.

The spelling of 215280020 in words is "two hundred fifteen million, two hundred eighty thousand, twenty".