28215432 has 64 divisors (see below), whose sum is σ = 89577600. Its totient is φ = 8061120.

The previous prime is 28215431. The next prime is 28215469. The reversal of 28215432 is 23451282.

It is a super-2 number, since 2×28215432² = 1592221205893248, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 28215396 and 28215405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28215431) 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, 7819 + ... + 10842.

It is an arithmetic number, because the mean of its divisors is an integer number (1399650).

Almost surely, 2^28215432 is an apocalyptic number.

It is an amenable number.

28215432 is an abundant number, since it is smaller than the sum of its proper divisors (61362168).

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

28215432 is a wasteful number, since it uses less digits than its factorization.

28215432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18683 (or 18673 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

The square root of 28215432 is about 5311.8200270717. The cubic root of 28215432 is about 304.4356922121.

The spelling of 28215432 in words is "twenty-eight million, two hundred fifteen thousand, four hundred thirty-two".