1247921346816 has 405 divisors, whose sum is σ = 3928337033621. Its totient is φ = 380923527168.

The previous prime is 1247921346797. The next prime is 1247921346821. The reversal of 1247921346816 is 6186431297421.

The square root of 1247921346816 is 1117104.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 207717177600 + 1040204169216 = 455760^2 + 1019904^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 33727603950 + ... + 33727603986.

Almost surely, 2^{1247921346816} is an apocalyptic number.

1247921346816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

1247921346816 is the 1117104-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1247921346816

1247921346816 is an abundant number, since it is smaller than the sum of its proper divisors (2680415686805).

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

1247921346816 is an frugal number, since it uses more digits than its factorization.

1247921346816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204 (or 59 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 54.

The spelling of 1247921346816 in words is "one trillion, two hundred forty-seven billion, nine hundred twenty-one million, three hundred forty-six thousand, eight hundred sixteen".