2147748218721 has 128 divisors (see below), whose sum is σ = 3910247976960. Its totient is φ = 1137130638336.

The previous prime is 2147748218711. The next prime is 2147748218743. The reversal of 2147748218721 is 1278128477412.

2147748218721 is a `hidden beast` number, since 2 + 14 + 77 + 482 + 1 + 87 + 2 + 1 = 666.

It is not a de Polignac number, because 2147748218721 - 2⁶ = 2147748218657 is a prime.

It is a super-2 number, since 2×2147748218721² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2147748218711) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 660234531 + ... + 660237783.

It is an arithmetic number, because the mean of its divisors is an integer number (30548812320).

Almost surely, 2^{2147748218721} is an apocalyptic number.

2147748218721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2147748218721 is a deficient number, since it is larger than the sum of its proper divisors (1762499758239).

2147748218721 is a wasteful number, since it uses less digits than its factorization.

2147748218721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6420 (or 6414 counting only the distinct ones).

The product of its digits is 2809856, while the sum is 54.

The spelling of 2147748218721 in words is "two trillion, one hundred forty-seven billion, seven hundred forty-eight million, two hundred eighteen thousand, seven hundred twenty-one".