215428786939 has 4 divisors (see below), whose sum is σ = 221251186624. Its totient is φ = 209606387256.

The previous prime is 215428786907. The next prime is 215428786949. The reversal of 215428786939 is 939687824512.

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

It is a cyclic number.

It is not a de Polignac number, because 215428786939 - 2⁵ = 215428786907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215428786949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2911199787 + ... + 2911199860.

It is an arithmetic number, because the mean of its divisors is an integer number (55312796656).

Almost surely, 2^215428786939 is an apocalyptic number.

215428786939 is a deficient number, since it is larger than the sum of its proper divisors (5822399685).

215428786939 is an equidigital number, since it uses as much as digits as its factorization.

215428786939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5822399684.

The product of its digits is 52254720, while the sum is 64.

The spelling of 215428786939 in words is "two hundred fifteen billion, four hundred twenty-eight million, seven hundred eighty-six thousand, nine hundred thirty-nine".