287381890 has 16 divisors (see below), whose sum is σ = 523101240. Its totient is φ = 113660800.

The previous prime is 287381869. The next prime is 287381893. The reversal of 287381890 is 98183782.

287381890 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 189035001 + 98346889 = 13749^2 + 9917^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 287381890.

It is not an unprimeable number, because it can be changed into a prime (287381893) 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, 160561 + ... + 162340.

Almost surely, 2^287381890 is an apocalyptic number.

287381890 is a deficient number, since it is larger than the sum of its proper divisors (235719350).

287381890 is a wasteful number, since it uses less digits than its factorization.

287381890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322997.

The product of its (nonzero) digits is 193536, while the sum is 46.

The square root of 287381890 is about 16952.3417261451. The cubic root of 287381890 is about 659.9126682733.

It can be divided in two parts, 28738 and 1890, that added together give a triangular number (30628 = T₂₄₇).

The spelling of 287381890 in words is "two hundred eighty-seven million, three hundred eighty-one thousand, eight hundred ninety".