287990640 has 300 divisors, whose sum is σ = 1164820536. Its totient is φ = 65753856.

The previous prime is 287990639. The next prime is 287990641. The reversal of 287990640 is 46099782.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (287990639) and next prime (287990641).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (287990641) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 317067 + ... + 317973.

Almost surely, 2^287990640 is an apocalyptic number.

287990640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 287990640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (582410268).

287990640 is an abundant number, since it is smaller than the sum of its proper divisors (876829896).

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

287990640 is a wasteful number, since it uses less digits than its factorization.

287990640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 946 (or 924 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 287990640 is about 16970.2869745918. The cubic root of 287990640 is about 660.3782955257.

The spelling of 287990640 in words is "two hundred eighty-seven million, nine hundred ninety thousand, six hundred forty".