28913621 has 8 divisors (see below), whose sum is σ = 31975104. Its totient is φ = 25924320.

The previous prime is 28913581. The next prime is 28913623. The reversal of 28913621 is 12631982.

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 28913621 - 2¹⁴ = 28897237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28913623) 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, 17201 + ... + 18806.

It is an arithmetic number, because the mean of its divisors is an integer number (3996888).

Almost surely, 2^28913621 is an apocalyptic number.

It is an amenable number.

28913621 is a deficient number, since it is larger than the sum of its proper divisors (3061483).

28913621 is a wasteful number, since it uses less digits than its factorization.

28913621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36091.

The product of its digits is 5184, while the sum is 32.

The square root of 28913621 is about 5377.1387372840. The cubic root of 28913621 is about 306.9263405211.

The spelling of 28913621 in words is "twenty-eight million, nine hundred thirteen thousand, six hundred twenty-one".