1215973 has 4 divisors (see below), whose sum is σ = 1326528. Its totient is φ = 1105420.

The previous prime is 1215923. The next prime is 1216009. The reversal of 1215973 is 3795121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3795121 = 11 ⋅345011.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1215973 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215923) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 55261 + ... + 55282.

It is an arithmetic number, because the mean of its divisors is an integer number (331632).

2^1215973 is an apocalyptic number.

It is an amenable number.

1215973 is a deficient number, since it is larger than the sum of its proper divisors (110555).

1215973 is a wasteful number, since it uses less digits than its factorization.

1215973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110554.

The product of its digits is 1890, while the sum is 28.

The square root of 1215973 is about 1102.7116576875. The cubic root of 1215973 is about 106.7352759557.

The spelling of 1215973 in words is "one million, two hundred fifteen thousand, nine hundred seventy-three".