1215988 has 6 divisors (see below), whose sum is σ = 2127986. Its totient is φ = 607992.

The previous prime is 1215923. The next prime is 1216009. The reversal of 1215988 is 8895121.

It can be written as a sum of positive squares in only one way, i.e., 1024144 + 191844 = 1012^2 + 438^2 .

It is a super-2 number, since 2×1215988² = 2957253632288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 151995 + ... + 152002.

2^1215988 is an apocalyptic number.

It is an amenable number.

1215988 is a deficient number, since it is larger than the sum of its proper divisors (911998).

1215988 is a wasteful number, since it uses less digits than its factorization.

1215988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304001 (or 303999 counting only the distinct ones).

The product of its digits is 5760, while the sum is 34.

The square root of 1215988 is about 1102.7184590819. The cubic root of 1215988 is about 106.7357148422.

The spelling of 1215988 in words is "one million, two hundred fifteen thousand, nine hundred eighty-eight".