285740639 has 4 divisors (see below), whose sum is σ = 300779640. Its totient is φ = 270701640.

The previous prime is 285740629. The next prime is 285740657. The reversal of 285740639 is 936047582.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 285740639 - 2¹² = 285736543 is a prime.

It is a super-2 number, since 2×285740639² = 163295425552256642, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 285740639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285740629) 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, 7519472 + ... + 7519509.

It is an arithmetic number, because the mean of its divisors is an integer number (75194910).

Almost surely, 2^285740639 is an apocalyptic number.

285740639 is a deficient number, since it is larger than the sum of its proper divisors (15039001).

285740639 is a wasteful number, since it uses less digits than its factorization.

285740639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15039000.

The product of its (nonzero) digits is 362880, while the sum is 44.

The square root of 285740639 is about 16903.8646172998. The cubic root of 285740639 is about 658.6540054099.

The spelling of 285740639 in words is "two hundred eighty-five million, seven hundred forty thousand, six hundred thirty-nine".