1206221520 has 80 divisors (see below), whose sum is σ = 4273476480. Its totient is φ = 275707392.

The previous prime is 1206221507. The next prime is 1206221531. The reversal of 1206221520 is 251226021.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×1206221520² = 2909940710622220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 357315 + ... + 360674.

It is an arithmetic number, because the mean of its divisors is an integer number (53418456).

Almost surely, 2^1206221520 is an apocalyptic number.

1206221520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1206221520 is an abundant number, since it is smaller than the sum of its proper divisors (3067254960).

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

1206221520 is a wasteful number, since it uses less digits than its factorization.

1206221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 718012 (or 718006 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 1206221520 is about 34730.6999641528. The cubic root of 1206221520 is about 1064.4918910160.

Adding to 1206221520 its reverse (251226021), we get a palindrome (1457447541).

The spelling of 1206221520 in words is "one billion, two hundred six million, two hundred twenty-one thousand, five hundred twenty".