28973240 has 16 divisors (see below), whose sum is σ = 65189880. Its totient is φ = 11589280.

The previous prime is 28973239. The next prime is 28973249. The reversal of 28973240 is 4237982.

It is a self number, because there is not a number n which added to its sum of digits gives 28973240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28973249) 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, 362126 + ... + 362205.

Almost surely, 2^28973240 is an apocalyptic number.

28973240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28973240 is an abundant number, since it is smaller than the sum of its proper divisors (36216640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28973240 is a wasteful number, since it uses less digits than its factorization.

28973240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724342 (or 724338 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 28973240 is about 5382.6796300727. The cubic root of 28973240 is about 307.1371532588.

The spelling of 28973240 in words is "twenty-eight million, nine hundred seventy-three thousand, two hundred forty".