1215021551145 has 16 divisors (see below), whose sum is σ = 1944061109952. Its totient is φ = 648002617920.

The previous prime is 1215021551119. The next prime is 1215021551207. The reversal of 1215021551145 is 5411551205121.

It is a happy number.

It is not a de Polignac number, because 1215021551145 - 2⁵ = 1215021551113 is a prime.

It is a super-2 number, since 2×1215021551145² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 663099 + ... + 1694031.

It is an arithmetic number, because the mean of its divisors is an integer number (121503819372).

Almost surely, 2^{1215021551145} is an apocalyptic number.

1215021551145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1215021551145 is a deficient number, since it is larger than the sum of its proper divisors (729039558807).

1215021551145 is a wasteful number, since it uses less digits than its factorization.

1215021551145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1109512.

The product of its (nonzero) digits is 10000, while the sum is 33.

Adding to 1215021551145 its reverse (5411551205121), we get a palindrome (6626572756266).

The spelling of 1215021551145 in words is "one trillion, two hundred fifteen billion, twenty-one million, five hundred fifty-one thousand, one hundred forty-five".