28663635 has 128 divisors (see below), whose sum is σ = 65028096. Its totient is φ = 10391040.

The previous prime is 28663631. The next prime is 28663639. The reversal of 28663635 is 53636682.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28663631) and next prime (28663639).

It is not a de Polignac number, because 28663635 - 2² = 28663631 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a junction number, because it is equal to n+sod(n) for n = 28663593 and 28663602.

It is not an unprimeable number, because it can be changed into a prime (28663631) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 345304 + ... + 345386.

It is an arithmetic number, because the mean of its divisors is an integer number (508032).

Almost surely, 2^28663635 is an apocalyptic number.

28663635 is an abundant number, since it is smaller than the sum of its proper divisors (36364461).

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

28663635 is a wasteful number, since it uses less digits than its factorization.

28663635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145.

The product of its digits is 155520, while the sum is 39.

The square root of 28663635 is about 5353.8430122670. The cubic root of 28663635 is about 306.0392213385.

The spelling of 28663635 in words is "twenty-eight million, six hundred sixty-three thousand, six hundred thirty-five".