1147385887921 has 81 divisors (see below), whose sum is σ = 1473698679201. Its totient is φ = 890314746048.

The previous prime is 1147385887903. The next prime is 1147385887939. The reversal of 1147385887921 is 1297885837411.

The square root of 1147385887921 is 1071161.

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

It is an interprime number because it is at equal distance from previous prime (1147385887903) and next prime (1147385887939).

It can be written as a sum of positive squares in 4 ways, for example, as 620983400625 + 526402487296 = 788025^2 + 725536^2 .

It is not a de Polignac number, because 1147385887921 - 2⁷ = 1147385887793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1147385884921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 7700576355 + ... + 7700576503.

Almost surely, 2^{1147385887921} is an apocalyptic number.

1147385887921 is the 1071161-st square number.

1147385887921 is the 535581-st centered octagonal number.

It is an amenable number.

1147385887921 is a deficient number, since it is larger than the sum of its proper divisors (326312791280).

1147385887921 is an frugal number, since it uses more digits than its factorization.

1147385887921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496 (or 248 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 64.

Multiplying 1147385887921 by its sum of digits (64), we get a square (73432696826944 = 8569288²).

The spelling of 1147385887921 in words is "one trillion, one hundred forty-seven billion, three hundred eighty-five million, eight hundred eighty-seven thousand, nine hundred twenty-one".