287640738 has 192 divisors, whose sum is σ = 819486720. Its totient is φ = 70761600.

The previous prime is 287640713. The next prime is 287640739. The reversal of 287640738 is 837046782.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 287640693 and 287640702.

It is not an unprimeable number, because it can be changed into a prime (287640739) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3640983 + ... + 3641061.

It is an arithmetic number, because the mean of its divisors is an integer number (4268160).

Almost surely, 2^287640738 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 287640738, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409743360).

287640738 is an abundant number, since it is smaller than the sum of its proper divisors (531845982).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

287640738 is a wasteful number, since it uses less digits than its factorization.

287640738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The square root of 287640738 is about 16959.9745872451. The cubic root of 287640738 is about 660.1107389942.

The spelling of 287640738 in words is "two hundred eighty-seven million, six hundred forty thousand, seven hundred thirty-eight".