280221381 has 24 divisors (see below), whose sum is σ = 442266240. Its totient is φ = 169560000.

The previous prime is 280221371. The next prime is 280221401. The reversal of 280221381 is 183122082.

280221381 is a `hidden beast` number, since 280 + 2 + 2 + 1 + 381 = 666.

It is not a de Polignac number, because 280221381 - 2¹⁰ = 280220357 is a prime.

It is a super-2 number, since 2×280221381² = 157048044739094322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280221301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72465 + ... + 76233.

It is an arithmetic number, because the mean of its divisors is an integer number (18427760).

Almost surely, 2^280221381 is an apocalyptic number.

It is an amenable number.

280221381 is a deficient number, since it is larger than the sum of its proper divisors (162044859).

280221381 is a wasteful number, since it uses less digits than its factorization.

280221381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4537 (or 4534 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 280221381 is about 16739.8142462812. The cubic root of 280221381 is about 654.3856337437.

It can be divided in two parts, 28022 and 1381, that added together give a triangular number (29403 = T₂₄₂).

The spelling of 280221381 in words is "two hundred eighty million, two hundred twenty-one thousand, three hundred eighty-one".