28531470 has 64 divisors (see below), whose sum is σ = 77137920. Its totient is φ = 6691200.

The previous prime is 28531463. The next prime is 28531471. The reversal of 28531470 is 7413582.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28531471) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8836 + ... + 11624.

It is an arithmetic number, because the mean of its divisors is an integer number (1205280).

Almost surely, 2^28531470 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28531470, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38568960).

28531470 is an abundant number, since it is smaller than the sum of its proper divisors (48606450).

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

28531470 is a wasteful number, since it uses less digits than its factorization.

28531470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2841.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 28531470 is about 5341.4857483663. The cubic root of 28531470 is about 305.5681250048.

The spelling of 28531470 in words is "twenty-eight million, five hundred thirty-one thousand, four hundred seventy".