1215664 has 10 divisors (see below), whose sum is σ = 2355380. Its totient is φ = 607824.

The previous prime is 1215649. The next prime is 1215673. The reversal of 1215664 is 4665121.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37974 + ... + 38005.

It is an arithmetic number, because the mean of its divisors is an integer number (235538).

2^1215664 is an apocalyptic number.

It is an amenable number.

1215664 is a deficient number, since it is larger than the sum of its proper divisors (1139716).

1215664 is an equidigital number, since it uses as much as digits as its factorization.

1215664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75987 (or 75981 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The square root of 1215664 is about 1102.5715396291. The cubic root of 1215664 is about 106.7262340898.

The spelling of 1215664 in words is "one million, two hundred fifteen thousand, six hundred sixty-four".