1221735 has 16 divisors (see below), whose sum is σ = 1981440. Its totient is φ = 642720.

The previous prime is 1221707. The next prime is 1221749. The reversal of 1221735 is 5371221.

It is not a de Polignac number, because 1221735 - 2⁹ = 1221223 is a prime.

It is a congruent number.

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, 670 + ... + 1700.

It is an arithmetic number, because the mean of its divisors is an integer number (123840).

2^1221735 is an apocalyptic number.

1221735 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1221735 is a deficient number, since it is larger than the sum of its proper divisors (759705).

1221735 is a wasteful number, since it uses less digits than its factorization.

1221735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1118.

The product of its digits is 420, while the sum is 21.

The square root of 1221735 is about 1105.3212202794. The cubic root of 1221735 is about 106.9036020025.

Adding to 1221735 its reverse (5371221), we get a palindrome (6592956).

The spelling of 1221735 in words is "one million, two hundred twenty-one thousand, seven hundred thirty-five".