28278774215 has 8 divisors (see below), whose sum is σ = 34851678720. Its totient is φ = 22011586272.

The previous prime is 28278774187. The next prime is 28278774239. The reversal of 28278774215 is 51247787282.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28278774215 is a prime.

It is a super-2 number, since 2×28278774215² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76428935 + ... + 76429304.

It is an arithmetic number, because the mean of its divisors is an integer number (4356459840).

Almost surely, 2^28278774215 is an apocalyptic number.

28278774215 is a deficient number, since it is larger than the sum of its proper divisors (6572904505).

28278774215 is a wasteful number, since it uses less digits than its factorization.

28278774215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152858281.

The product of its digits is 3512320, while the sum is 53.

The spelling of 28278774215 in words is "twenty-eight billion, two hundred seventy-eight million, seven hundred seventy-four thousand, two hundred fifteen".