215390340 has 336 divisors, whose sum is σ = 793255680. Its totient is φ = 48522240.

The previous prime is 215390339. The next prime is 215390347. The reversal of 215390340 is 43093512.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (215390347) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 2726421 + ... + 2726499.

It is an arithmetic number, because the mean of its divisors is an integer number (2360880).

Almost surely, 2^215390340 is an apocalyptic number.

215390340 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 215390340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396627840).

215390340 is an abundant number, since it is smaller than the sum of its proper divisors (577865340).

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

215390340 is a wasteful number, since it uses less digits than its factorization.

215390340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 215390340 is about 14676.1827462048. The cubic root of 215390340 is about 599.4349680652.

The spelling of 215390340 in words is "two hundred fifteen million, three hundred ninety thousand, three hundred forty".