287800061 has 4 divisors (see below), whose sum is σ = 288236124. Its totient is φ = 287364000.

The previous prime is 287800043. The next prime is 287800109. The reversal of 287800061 is 160008782.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 160008782 = 2 ⋅80004391.

It can be written as a sum of positive squares in 2 ways, for example, as 141752836 + 146047225 = 11906^2 + 12085^2 .

It is a cyclic number.

It is not a de Polignac number, because 287800061 - 2¹⁸ = 287537917 is a prime.

It is a super-2 number, since 2×287800061² = 165657750223207442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (287800561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 217040 + ... + 218361.

It is an arithmetic number, because the mean of its divisors is an integer number (72059031).

Almost surely, 2^287800061 is an apocalyptic number.

It is an amenable number.

287800061 is a deficient number, since it is larger than the sum of its proper divisors (436063).

287800061 is an equidigital number, since it uses as much as digits as its factorization.

287800061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436062.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 287800061 is about 16964.6709664526. The cubic root of 287800061 is about 660.2325940232.

The spelling of 287800061 in words is "two hundred eighty-seven million, eight hundred thousand, sixty-one".