1220143 has 4 divisors (see below), whose sum is σ = 1222560. Its totient is φ = 1217728.
The previous prime is 1220099. The next prime is 1220147. The reversal of 1220143 is 3410221.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1220143 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (1220147) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 130 + ... + 1567.
It is an arithmetic number, because the mean of its divisors is an integer number (305640).
21220143 is an apocalyptic number.
1220143 is a deficient number, since it is larger than the sum of its proper divisors (2417).
1220143 is an equidigital number, since it uses as much as digits as its factorization.
1220143 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 2416.
The product of its (nonzero) digits is 48, while the sum is 13.
The square root of 1220143 is about 1104.6008328804. The cubic root of 1220143 is about 106.8571477084.
Adding to 1220143 its reverse (3410221), we get a palindrome (4630364).
The spelling of 1220143 in words is "one million, two hundred twenty thousand, one hundred forty-three".
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