1215787670816 has 24 divisors (see below), whose sum is σ = 2397564680364. Its totient is φ = 606882355200.

The previous prime is 1215787670807. The next prime is 1215787670863. The reversal of 1215787670816 is 6180767875121.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1146826810000 + 68960860816 = 1070900^2 + 262604^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31589225 + ... + 31627688.

Almost surely, 2^{1215787670816} is an apocalyptic number.

1215787670816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1215787670816 is a deficient number, since it is larger than the sum of its proper divisors (1181777009548).

1215787670816 is an equidigital number, since it uses as much as digits as its factorization.

1215787670816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63217524 (or 63217516 counting only the distinct ones).

The product of its (nonzero) digits is 7902720, while the sum is 59.

The spelling of 1215787670816 in words is "one trillion, two hundred fifteen billion, seven hundred eighty-seven million, six hundred seventy thousand, eight hundred sixteen".