1215401443155 has 32 divisors (see below), whose sum is σ = 2182106905920. Its totient is φ = 641796134400.

The previous prime is 1215401443147. The next prime is 1215401443183. The reversal of 1215401443155 is 5513441045121.

1215401443155 is a `hidden beast` number, since 1 + 21 + 5 + 40 + 1 + 443 + 155 = 666.

It is not a de Polignac number, because 1215401443155 - 2³ = 1215401443147 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44555542 + ... + 44582811.

It is an arithmetic number, because the mean of its divisors is an integer number (68190840810).

Almost surely, 2^{1215401443155} is an apocalyptic number.

1215401443155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1215401443155 is a deficient number, since it is larger than the sum of its proper divisors (966705462765).

1215401443155 is a wasteful number, since it uses less digits than its factorization.

1215401443155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89138468 (or 89138462 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

Adding to 1215401443155 its reverse (5513441045121), we get a palindrome (6728842488276).

The spelling of 1215401443155 in words is "one trillion, two hundred fifteen billion, four hundred one million, four hundred forty-three thousand, one hundred fifty-five".