1287764 has 12 divisors (see below), whose sum is σ = 2306304. Its totient is φ = 628824.

The previous prime is 1287761. The next prime is 1287787. The reversal of 1287764 is 4677821.

It is a happy number.

It is a super-2 number, since 2×1287764² = 3316672239392, which contains 22 as substring.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287761) 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, 3572 + ... + 3915.

It is an arithmetic number, because the mean of its divisors is an integer number (192192).

2^1287764 is an apocalyptic number.

It is an amenable number.

1287764 is a deficient number, since it is larger than the sum of its proper divisors (1018540).

1287764 is a wasteful number, since it uses less digits than its factorization.

1287764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7534 (or 7532 counting only the distinct ones).

The product of its digits is 18816, while the sum is 35.

The square root of 1287764 is about 1134.7968981276. The cubic root of 1287764 is about 108.7957908190.

The spelling of 1287764 in words is "one million, two hundred eighty-seven thousand, seven hundred sixty-four".