1242820 has 12 divisors (see below), whose sum is σ = 2609964. Its totient is φ = 497120.

The previous prime is 1242817. The next prime is 1242823. The reversal of 1242820 is 282421.

It is an interprime number because it is at equal distance from previous prime (1242817) and next prime (1242823).

It can be written as a sum of positive squares in 2 ways, for example, as 788544 + 454276 = 888^2 + 674^2 .

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (1242823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31051 + ... + 31090.

It is an arithmetic number, because the mean of its divisors is an integer number (217497).

2^1242820 is an apocalyptic number.

1242820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1242820 is an abundant number, since it is smaller than the sum of its proper divisors (1367144).

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

1242820 is a wasteful number, since it uses less digits than its factorization.

1242820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62150 (or 62148 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1242820 is about 1114.8183708569. The cubic root of 1242820 is about 107.5150871199.

The spelling of 1242820 in words is "one million, two hundred forty-two thousand, eight hundred twenty".