280399155 has 16 divisors (see below), whose sum is σ = 450088704. Its totient is φ = 149062880.

The previous prime is 280399117. The next prime is 280399157. The reversal of 280399155 is 551993082.

It is not a de Polignac number, because 280399155 - 2⁷ = 280399027 is a prime.

It is a super-2 number, since 2×280399155² = 157247372249428050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (280399157) 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, 25389 + ... + 34718.

It is an arithmetic number, because the mean of its divisors is an integer number (28130544).

Almost surely, 2^280399155 is an apocalyptic number.

280399155 is a deficient number, since it is larger than the sum of its proper divisors (169689549).

280399155 is a wasteful number, since it uses less digits than its factorization.

280399155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60426.

The product of its (nonzero) digits is 97200, while the sum is 42.

The square root of 280399155 is about 16745.1233199400. The cubic root of 280399155 is about 654.5239864504.

The spelling of 280399155 in words is "two hundred eighty million, three hundred ninety-nine thousand, one hundred fifty-five".