1215890 has 32 divisors (see below), whose sum is σ = 2419200. Its totient is φ = 437184.

The previous prime is 1215881. The next prime is 1215899. The reversal of 1215890 is 985121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1215881) and next prime (1215899).

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1215899) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6011 + ... + 6209.

It is an arithmetic number, because the mean of its divisors is an integer number (75600).

2^1215890 is an apocalyptic number.

1215890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1215890 is a deficient number, since it is larger than the sum of its proper divisors (1203310).

1215890 is a wasteful number, since it uses less digits than its factorization.

1215890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 1215890 is about 1102.6740225470. The cubic root of 1215890 is about 106.7328473849.

The spelling of 1215890 in words is "one million, two hundred fifteen thousand, eight hundred ninety".