1221507 has 32 divisors (see below), whose sum is σ = 2165760. Its totient is φ = 665280.

The previous prime is 1221503. The next prime is 1221523. The reversal of 1221507 is 7051221.

It is not a de Polignac number, because 1221507 - 2² = 1221503 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221507.

It is not an unprimeable number, because it can be changed into a prime (1221503) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4207 + ... + 4487.

It is an arithmetic number, because the mean of its divisors is an integer number (67680).

2^1221507 is an apocalyptic number.

1221507 is a deficient number, since it is larger than the sum of its proper divisors (944253).

1221507 is a wasteful number, since it uses less digits than its factorization.

1221507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 1221507 is about 1105.2180780280. The cubic root of 1221507 is about 106.8969514774.

Adding to 1221507 its reverse (7051221), we get a palindrome (8272728).

It can be divided in two parts, 1221 and 507, that added together give a cube (1728 = 12³).

The spelling of 1221507 in words is "one million, two hundred twenty-one thousand, five hundred seven".