215780293 has 2 divisors, whose sum is σ = 215780294. Its totient is φ = 215780292.

The previous prime is 215780251. The next prime is 215780297. The reversal of 215780293 is 392087512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153338689 + 62441604 = 12383^2 + 7902^2 .

It is a cyclic number.

It is not a de Polignac number, because 215780293 - 2¹³ = 215772101 is a prime.

It is a super-2 number, since 2×215780293² = 93122269694331698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215780297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107890146 + 107890147.

It is an arithmetic number, because the mean of its divisors is an integer number (107890147).

Almost surely, 2^215780293 is an apocalyptic number.

It is an amenable number.

215780293 is a deficient number, since it is larger than the sum of its proper divisors (1).

215780293 is an equidigital number, since it uses as much as digits as its factorization.

215780293 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 215780293 is about 14689.4619710866. The cubic root of 215780293 is about 599.7964985790.

The spelling of 215780293 in words is "two hundred fifteen million, seven hundred eighty thousand, two hundred ninety-three".