28916291621 has 8 divisors (see below), whose sum is σ = 33048759744. Its totient is φ = 24784215840.

The previous prime is 28916291597. The next prime is 28916291629. The reversal of 28916291621 is 12619261982.

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 not a de Polignac number, because 28916291621 - 2¹⁸ = 28916029477 is a prime.

It is a super-2 number, since 2×28916291621² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28916291629) 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, 81866 + ... + 254036.

It is an arithmetic number, because the mean of its divisors is an integer number (4131094968).

Almost surely, 2^28916291621 is an apocalyptic number.

It is an amenable number.

28916291621 is a deficient number, since it is larger than the sum of its proper divisors (4132468123).

28916291621 is a wasteful number, since it uses less digits than its factorization.

28916291621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196171.

The product of its digits is 186624, while the sum is 47.

The spelling of 28916291621 in words is "twenty-eight billion, nine hundred sixteen million, two hundred ninety-one thousand, six hundred twenty-one".