147878721 has 12 divisors (see below), whose sum is σ = 217223760. Its totient is φ = 96914520.

The previous prime is 147878719. The next prime is 147878749. The reversal of 147878721 is 127878741.

It is not a de Polignac number, because 147878721 - 2¹ = 147878719 is a prime.

It is a super-2 number, since 2×147878721² = 43736232249191682, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (147878761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 138715 + ... + 139776.

It is an arithmetic number, because the mean of its divisors is an integer number (18101980).

Almost surely, 2^147878721 is an apocalyptic number.

It is an amenable number.

147878721 is a deficient number, since it is larger than the sum of its proper divisors (69345039).

147878721 is a wasteful number, since it uses less digits than its factorization.

147878721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278556 (or 278553 counting only the distinct ones).

The product of its digits is 175616, while the sum is 45.

The square root of 147878721 is about 12160.5395028346. The cubic root of 147878721 is about 528.8127226366.

The spelling of 147878721 in words is "one hundred forty-seven million, eight hundred seventy-eight thousand, seven hundred twenty-one".