1215520400442 has 96 divisors (see below), whose sum is σ = 2718617416704. Its totient is φ = 361007539200.

The previous prime is 1215520400429. The next prime is 1215520400467. The reversal of 1215520400442 is 2440040255121.

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 47 ways as a sum of consecutive naturals, for example, 54153942 + ... + 54176382.

It is an arithmetic number, because the mean of its divisors is an integer number (28318931424).

Almost surely, 2^{1215520400442} is an apocalyptic number.

1215520400442 is an abundant number, since it is smaller than the sum of its proper divisors (1503097016262).

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

1215520400442 is a wasteful number, since it uses less digits than its factorization.

1215520400442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23972 (or 23953 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 1215520400442 its reverse (2440040255121), we get a palindrome (3655560655563).

The spelling of 1215520400442 in words is "one trillion, two hundred fifteen billion, five hundred twenty million, four hundred thousand, four hundred forty-two".