28139964 has 24 divisors (see below), whose sum is σ = 69522768. Its totient is φ = 8828160.

The previous prime is 28139963. The next prime is 28139977. The reversal of 28139964 is 46993182.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28139963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68767 + ... + 69174.

It is an arithmetic number, because the mean of its divisors is an integer number (2896782).

Almost surely, 2^28139964 is an apocalyptic number.

It is an amenable number.

28139964 is an abundant number, since it is smaller than the sum of its proper divisors (41382804).

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

28139964 is a wasteful number, since it uses less digits than its factorization.

28139964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137965 (or 137963 counting only the distinct ones).

The product of its digits is 93312, while the sum is 42.

The square root of 28139964 is about 5304.7114907410. The cubic root of 28139964 is about 304.1640244803.

The spelling of 28139964 in words is "twenty-eight million, one hundred thirty-nine thousand, nine hundred sixty-four".