28137945 has 48 divisors (see below), whose sum is σ = 50944320. Its totient is φ = 13242240.

The previous prime is 28137943. The next prime is 28137971. The reversal of 28137945 is 54973182.

It is not a de Polignac number, because 28137945 - 2¹ = 28137943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28137943) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 66946 + ... + 67364.

It is an arithmetic number, because the mean of its divisors is an integer number (1061340).

Almost surely, 2^28137945 is an apocalyptic number.

It is an amenable number.

28137945 is a deficient number, since it is larger than the sum of its proper divisors (22806375).

28137945 is a wasteful number, since it uses less digits than its factorization.

28137945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 486 (or 475 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 28137945 is about 5304.5211848008. The cubic root of 28137945 is about 304.1567498695.

It can be divided in two parts, 281 and 37945, that added together give a triangular number (38226 = T₂₇₆).

The spelling of 28137945 in words is "twenty-eight million, one hundred thirty-seven thousand, nine hundred forty-five".