28712087326561 has 4 divisors (see below), whose sum is σ = 28714364088624. Its totient is φ = 28709810564500.

The previous prime is 28712087326543. The next prime is 28712087326577. The reversal of 28712087326561 is 16562378021782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28712087326561 - 2²⁷ = 28711953108833 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28712087326496 and 28712087326505.

It is not an unprimeable number, because it can be changed into a prime (28712087326061) 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, 1138362115 + ... + 1138387336.

It is an arithmetic number, because the mean of its divisors is an integer number (7178591022156).

Almost surely, 2^{28712087326561} is an apocalyptic number.

It is an amenable number.

28712087326561 is a deficient number, since it is larger than the sum of its proper divisors (2276762063).

28712087326561 is a wasteful number, since it uses less digits than its factorization.

28712087326561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2276762062.

The product of its (nonzero) digits is 13547520, while the sum is 58.

The spelling of 28712087326561 in words is "twenty-eight trillion, seven hundred twelve billion, eighty-seven million, three hundred twenty-six thousand, five hundred sixty-one".