1216945 has 16 divisors (see below), whose sum is σ = 1572480. Its totient is φ = 900864.

The previous prime is 1216939. The next prime is 1216951. The reversal of 1216945 is 5496121.

It is an interprime number because it is at equal distance from previous prime (1216939) and next prime (1216951).

It is not a de Polignac number, because 1216945 - 2³ = 1216937 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8686 + ... + 8824.

It is an arithmetic number, because the mean of its divisors is an integer number (98280).

2^1216945 is an apocalyptic number.

It is an amenable number.

1216945 is a deficient number, since it is larger than the sum of its proper divisors (355535).

1216945 is a wasteful number, since it uses less digits than its factorization.

1216945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264.

The product of its digits is 2160, while the sum is 28.

The square root of 1216945 is about 1103.1523013619. The cubic root of 1216945 is about 106.7637083460.

The spelling of 1216945 in words is "one million, two hundred sixteen thousand, nine hundred forty-five".