215009428 has 24 divisors (see below), whose sum is σ = 405296640. Its totient is φ = 99512160.

The previous prime is 215009413. The next prime is 215009429. The reversal of 215009428 is 824900512.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a self number, because there is not a number n which added to its sum of digits gives 215009428.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215009429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34843 + ... + 40546.

It is an arithmetic number, because the mean of its divisors is an integer number (16887360).

Almost surely, 2^215009428 is an apocalyptic number.

It is an amenable number.

215009428 is a deficient number, since it is larger than the sum of its proper divisors (190287212).

215009428 is a wasteful number, since it uses less digits than its factorization.

215009428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75447 (or 75445 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 215009428 is about 14663.1997872224. The cubic root of 215009428 is about 599.0813980388.

The spelling of 215009428 in words is "two hundred fifteen million, nine thousand, four hundred twenty-eight".