1215212655 has 8 divisors (see below), whose sum is σ = 1944340272. Its totient is φ = 648113408.

The previous prime is 1215212651. The next prime is 1215212693. The reversal of 1215212655 is 5562125121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1215212655 - 2² = 1215212651 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215212651) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 40507074 + ... + 40507103.

It is an arithmetic number, because the mean of its divisors is an integer number (243042534).

Almost surely, 2^1215212655 is an apocalyptic number.

1215212655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1215212655 is a deficient number, since it is larger than the sum of its proper divisors (729127617).

1215212655 is an equidigital number, since it uses as much as digits as its factorization.

1215212655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81014185.

The product of its digits is 6000, while the sum is 30.

The square root of 1215212655 is about 34859.9003871210. The cubic root of 1215212655 is about 1067.1302421306.

Adding to 1215212655 its reverse (5562125121), we get a palindrome (6777337776).

The spelling of 1215212655 in words is "one billion, two hundred fifteen million, two hundred twelve thousand, six hundred fifty-five".