28072340 has 12 divisors (see below), whose sum is σ = 58951956. Its totient is φ = 11228928.

The previous prime is 28072339. The next prime is 28072361. The reversal of 28072340 is 4327082.

It can be written as a sum of positive squares in 2 ways, for example, as 17405584 + 10666756 = 4172^2 + 3266^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 701789 + ... + 701828.

It is an arithmetic number, because the mean of its divisors is an integer number (4912663).

Almost surely, 2^28072340 is an apocalyptic number.

28072340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28072340 is an abundant number, since it is smaller than the sum of its proper divisors (30879616).

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

28072340 is a wasteful number, since it uses less digits than its factorization.

28072340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1403626 (or 1403624 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 28072340 is about 5298.3337003250. Note that the first 3 decimals coincide. The cubic root of 28072340 is about 303.9201804522.

The spelling of 28072340 in words is "twenty-eight million, seventy-two thousand, three hundred forty".