1231812 has 18 divisors (see below), whose sum is σ = 3113838. Its totient is φ = 410592.

The previous prime is 1231807. The next prime is 1231817. The reversal of 1231812 is 2181321.

It is an interprime number because it is at equal distance from previous prime (1231807) and next prime (1231817).

It can be written as a sum of positive squares in only one way, i.e., 1218816 + 12996 = 1104^2 + 114^2 .

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 not an unprimeable number, because it can be changed into a prime (1231817) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17073 + ... + 17144.

It is an arithmetic number, because the mean of its divisors is an integer number (172991).

2^1231812 is an apocalyptic number.

1231812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1231812 is an abundant number, since it is smaller than the sum of its proper divisors (1882026).

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

1231812 is a wasteful number, since it uses less digits than its factorization.

1231812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34227 (or 34222 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 1231812 is about 1109.8702626884. The cubic root of 1231812 is about 107.1967150178.

The spelling of 1231812 in words is "one million, two hundred thirty-one thousand, eight hundred twelve".