1215202251856 has 20 divisors (see below), whose sum is σ = 2354834489652. Its totient is φ = 607503028736.

The previous prime is 1215202251853. The next prime is 1215202251859. The reversal of 1215202251856 is 6581522025121.

It is an interprime number because it is at equal distance from previous prime (1215202251853) and next prime (1215202251859).

It can be written as a sum of positive squares in 2 ways, for example, as 485134538256 + 730067713600 = 696516^2 + 854440^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215202251853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6028825 + ... + 6227128.

Almost surely, 2^{1215202251856} is an apocalyptic number.

1215202251856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1215202251856 is a deficient number, since it is larger than the sum of its proper divisors (1139632237796).

1215202251856 is a wasteful number, since it uses less digits than its factorization.

1215202251856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12262158 (or 12262152 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 40.

Adding to 1215202251856 its reverse (6581522025121), we get a palindrome (7796724276977).

The spelling of 1215202251856 in words is "one trillion, two hundred fifteen billion, two hundred two million, two hundred fifty-one thousand, eight hundred fifty-six".