1200720420 has 72 divisors (see below), whose sum is σ = 3645338424. Its totient is φ = 319915008.

The previous prime is 1200720407. The next prime is 1200720431. The reversal of 1200720420 is 240270021.

It can be written as a sum of positive squares in 4 ways, for example, as 194435136 + 1006285284 = 13944^2 + 31722^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1200720393 and 1200720402.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 285372 + ... + 289548.

Almost surely, 2^1200720420 is an apocalyptic number.

1200720420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1200720420 is an abundant number, since it is smaller than the sum of its proper divisors (2444618004).

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

1200720420 is a wasteful number, since it uses less digits than its factorization.

1200720420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5789 (or 5784 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 1200720420 is about 34651.4129582042. The cubic root of 1200720420 is about 1062.8711823315.

Adding to 1200720420 its reverse (240270021), we get a palindrome (1440990441).

The spelling of 1200720420 in words is "one billion, two hundred million, seven hundred twenty thousand, four hundred twenty".