1220040 has 48 divisors (see below), whose sum is σ = 3966300. Its totient is φ = 325248.

The previous prime is 1220029. The next prime is 1220041. The reversal of 1220040 is 400221.

1220040 = T₁₈₅ + T₁₈₆ + ... + T₂₃₈.

It can be written as a sum of positive squares in 2 ways, for example, as 1153476 + 66564 = 1074^2 + 258^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (1220041) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1335 + ... + 2054.

2^1220040 is an apocalyptic number.

1220040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220040 is an abundant number, since it is smaller than the sum of its proper divisors (2746260).

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

1220040 is a wasteful number, since it uses less digits than its factorization.

1220040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3406 (or 3399 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 1220040 is about 1104.5542087195. The cubic root of 1220040 is about 106.8541407942.

Adding to 1220040 its reverse (400221), we get a palindrome (1620261).

The spelling of 1220040 in words is "one million, two hundred twenty thousand, forty".