28001554521 has 8 divisors (see below), whose sum is σ = 37968209760. Its totient is φ = 18351301152.

The previous prime is 28001554519. The next prime is 28001554523. The reversal of 28001554521 is 12545510082.

It is an interprime number because it is at equal distance from previous prime (28001554519) and next prime (28001554523).

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

It is not a de Polignac number, because 28001554521 - 2¹ = 28001554519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28001554523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79100260 + ... + 79100613.

It is an arithmetic number, because the mean of its divisors is an integer number (4746026220).

Almost surely, 2^28001554521 is an apocalyptic number.

It is an amenable number.

28001554521 is a deficient number, since it is larger than the sum of its proper divisors (9966655239).

28001554521 is a wasteful number, since it uses less digits than its factorization.

28001554521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158200935.

The product of its (nonzero) digits is 16000, while the sum is 33.

The spelling of 28001554521 in words is "twenty-eight billion, one million, five hundred fifty-four thousand, five hundred twenty-one".