1213864 has 8 divisors (see below), whose sum is σ = 2276010. Its totient is φ = 606928.

The previous prime is 1213841. The next prime is 1213873. The reversal of 1213864 is 4683121.

It can be written as a sum of positive squares in only one way, i.e., 902500 + 311364 = 950^2 + 558^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 75859 + ... + 75874.

2^1213864 is an apocalyptic number.

It is an amenable number.

1213864 is a deficient number, since it is larger than the sum of its proper divisors (1062146).

1213864 is a wasteful number, since it uses less digits than its factorization.

1213864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151739 (or 151735 counting only the distinct ones).

The product of its digits is 1152, while the sum is 25.

The square root of 1213864 is about 1101.7549636829. The cubic root of 1213864 is about 106.6735325442.

Adding to 1213864 its reverse (4683121), we get a palindrome (5896985).

The spelling of 1213864 in words is "one million, two hundred thirteen thousand, eight hundred sixty-four".