280528138 has 16 divisors (see below), whose sum is σ = 459841536. Its totient is φ = 127291840.

The previous prime is 280528133. The next prime is 280528139. The reversal of 280528138 is 831825082.

It is a junction number, because it is equal to n+sod(n) for n = 280528097 and 280528106.

It is not an unprimeable number, because it can be changed into a prime (280528133) 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, 2295 + ... + 23797.

It is an arithmetic number, because the mean of its divisors is an integer number (28740096).

Almost surely, 2^280528138 is an apocalyptic number.

280528138 is a deficient number, since it is larger than the sum of its proper divisors (179313398).

280528138 is a wasteful number, since it uses less digits than its factorization.

280528138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22109.

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 280528138 is about 16748.9742372481. The cubic root of 280528138 is about 654.6243309349.

The spelling of 280528138 in words is "two hundred eighty million, five hundred twenty-eight thousand, one hundred thirty-eight".