1220303720 has 16 divisors (see below), whose sum is σ = 2745683460. Its totient is φ = 488121472.

The previous prime is 1220303699. The next prime is 1220303759. The reversal of 1220303720 is 273030221.

It can be written as a sum of positive squares in 2 ways, for example, as 1203673636 + 16630084 = 34694^2 + 4078^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1220303692 and 1220303701.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15253757 + ... + 15253836.

Almost surely, 2^1220303720 is an apocalyptic number.

1220303720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220303720 is an abundant number, since it is smaller than the sum of its proper divisors (1525379740).

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

1220303720 is a wasteful number, since it uses less digits than its factorization.

1220303720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30507604 (or 30507600 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 1220303720 is about 34932.8458617388. The cubic root of 1220303720 is about 1068.6183932424.

Adding to 1220303720 its reverse (273030221), we get a palindrome (1493333941).

The spelling of 1220303720 in words is "one billion, two hundred twenty million, three hundred three thousand, seven hundred twenty".