28874131621 has 4 divisors (see below), whose sum is σ = 30129528672. Its totient is φ = 27618734572.

The previous prime is 28874131597. The next prime is 28874131651. The reversal of 28874131621 is 12613147882.

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 28874131621 - 2¹¹ = 28874129573 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28874131651) 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, 627698491 + ... + 627698536.

It is an arithmetic number, because the mean of its divisors is an integer number (7532382168).

Almost surely, 2^28874131621 is an apocalyptic number.

It is an amenable number.

28874131621 is a deficient number, since it is larger than the sum of its proper divisors (1255397051).

28874131621 is a wasteful number, since it uses less digits than its factorization.

28874131621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1255397050.

The product of its digits is 129024, while the sum is 43.

The spelling of 28874131621 in words is "twenty-eight billion, eight hundred seventy-four million, one hundred thirty-one thousand, six hundred twenty-one".