28157480 has 64 divisors (see below), whose sum is σ = 68841360. Its totient is φ = 10303488.

The previous prime is 28157477. The next prime is 28157483. The reversal of 28157480 is 8475182.

28157480 = 130² + 131² + ... + 442².

It is an interprime number because it is at equal distance from previous prime (28157477) and next prime (28157483).

It can be written as a sum of positive squares in 8 ways, for example, as 4401604 + 23755876 = 2098^2 + 4874^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 28157480.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28157483) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89804 + ... + 90116.

Almost surely, 2^28157480 is an apocalyptic number.

28157480 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 28157480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34420680).

28157480 is an abundant number, since it is smaller than the sum of its proper divisors (40683880).

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

28157480 is a wasteful number, since it uses less digits than its factorization.

28157480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510 (or 506 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 28157480 is about 5306.3622190725. The cubic root of 28157480 is about 304.2271213627.

The spelling of 28157480 in words is "twenty-eight million, one hundred fifty-seven thousand, four hundred eighty".