215105755728 has 20 divisors (see below), whose sum is σ = 555689869088. Its totient is φ = 71701918560.

The previous prime is 215105755721. The next prime is 215105755789. The reversal of 215105755728 is 827557501512.

It is a super-2 number, since 2×215105755728² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 4481369911 = 215105755728 / (2 + 1 + 5 + 1 + 0 + 5 + 7 + 5 + 5 + 7 + 2 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215105755721) 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, 2240684908 + ... + 2240685003.

Almost surely, 2^215105755728 is an apocalyptic number.

It is an amenable number.

215105755728 is an abundant number, since it is smaller than the sum of its proper divisors (340584113360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

215105755728 is a wasteful number, since it uses less digits than its factorization.

215105755728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4481369922 (or 4481369916 counting only the distinct ones).

The product of its (nonzero) digits is 980000, while the sum is 48.

The spelling of 215105755728 in words is "two hundred fifteen billion, one hundred five million, seven hundred fifty-five thousand, seven hundred twenty-eight".