215730901 has 4 divisors (see below), whose sum is σ = 228420972. Its totient is φ = 203040832.

The previous prime is 215730877. The next prime is 215730967. The reversal of 215730901 is 109037512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 201668401 + 14062500 = 14201^2 + 3750^2 .

It is a cyclic number.

It is not a de Polignac number, because 215730901 - 2¹¹ = 215728853 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 215730901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215730301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6345010 + ... + 6345043.

It is an arithmetic number, because the mean of its divisors is an integer number (57105243).

Almost surely, 2^215730901 is an apocalyptic number.

It is an amenable number.

215730901 is a deficient number, since it is larger than the sum of its proper divisors (12690071).

215730901 is a wasteful number, since it uses less digits than its factorization.

215730901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12690070.

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 215730901 is about 14687.7806696587. The cubic root of 215730901 is about 599.7507307150.

The spelling of 215730901 in words is "two hundred fifteen million, seven hundred thirty thousand, nine hundred one".