1221732 has 18 divisors (see below), whose sum is σ = 3088358. Its totient is φ = 407232.

The previous prime is 1221707. The next prime is 1221749. The reversal of 1221732 is 2371221.

It can be written as a sum of positive squares in only one way, i.e., 1218816 + 2916 = 1104^2 + 54^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16933 + ... + 17004.

2^1221732 is an apocalyptic number.

1221732 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221732 is an abundant number, since it is smaller than the sum of its proper divisors (1866626).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221732 is a wasteful number, since it uses less digits than its factorization.

1221732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33947 (or 33942 counting only the distinct ones).

The product of its digits is 168, while the sum is 18.

The square root of 1221732 is about 1105.3198632070. The cubic root of 1221732 is about 106.9035145010.

Adding to 1221732 its reverse (2371221), we get a palindrome (3592953).

It can be divided in two parts, 1221 and 732, that added together give a triangular number (1953 = T₆₂).

The spelling of 1221732 in words is "one million, two hundred twenty-one thousand, seven hundred thirty-two".