4891625721 has 72 divisors (see below), whose sum is σ = 7765729920. Its totient is φ = 3076006752.

The previous prime is 4891625659. The next prime is 4891625731. The reversal of 4891625721 is 1275261984.

4891625721 is a `hidden beast` number, since 489 + 162 + 5 + 7 + 2 + 1 = 666.

It is not a de Polignac number, because 4891625721 - 2⁶ = 4891625657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4891625731) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 8942370 + ... + 8942916.

It is an arithmetic number, because the mean of its divisors is an integer number (107857360).

Almost surely, 2^4891625721 is an apocalyptic number.

It is an amenable number.

4891625721 is a deficient number, since it is larger than the sum of its proper divisors (2874104199).

4891625721 is an frugal number, since it uses more digits than its factorization.

4891625721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647 (or 626 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 4891625721 is about 69940.1581425149. The cubic root of 4891625721 is about 1697.5311014074.

The spelling of 4891625721 in words is "four billion, eight hundred ninety-one million, six hundred twenty-five thousand, seven hundred twenty-one".