28649340 has 72 divisors (see below), whose sum is σ = 91487760. Its totient is φ = 7236864.

The previous prime is 28649339. The next prime is 28649377. The reversal of 28649340 is 4394682.

It is a happy number.

28649340 is a `hidden beast` number, since 2 + 8 + 649 + 3 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28649295 and 28649304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 769 + ... + 7608.

Almost surely, 2^28649340 is an apocalyptic number.

28649340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28649340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45743880).

28649340 is an abundant number, since it is smaller than the sum of its proper divisors (62838420).

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

28649340 is a wasteful number, since it uses less digits than its factorization.

28649340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8411 (or 8406 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 28649340 is about 5352.5078234413. The cubic root of 28649340 is about 305.9883373743.

The spelling of 28649340 in words is "twenty-eight million, six hundred forty-nine thousand, three hundred forty".