4245587721 has 6 divisors (see below), whose sum is σ = 6132515610. Its totient is φ = 2830391808.

The previous prime is 4245587713. The next prime is 4245587729. The reversal of 4245587721 is 1277855424.

4245587721 is a `hidden beast` number, since 4 + 2 + 4 + 558 + 77 + 21 = 666.

4245587721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (4245587713) and next prime (4245587729).

It can be written as a sum of positive squares in only one way, i.e., 4040382096 + 205205625 = 63564^2 + 14325^2 .

It is not a de Polignac number, because 4245587721 - 2³ = 4245587713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4245587729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 235865976 + ... + 235865993.

It is an arithmetic number, because the mean of its divisors is an integer number (1022085935).

Almost surely, 2^4245587721 is an apocalyptic number.

It is an amenable number.

4245587721 is a deficient number, since it is larger than the sum of its proper divisors (1886927889).

4245587721 is a wasteful number, since it uses less digits than its factorization.

4245587721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471731975 (or 471731972 counting only the distinct ones).

The product of its digits is 627200, while the sum is 45.

The square root of 4245587721 is about 65158.1746291285. The cubic root of 4245587721 is about 1619.2451547330.

The spelling of 4245587721 in words is "four billion, two hundred forty-five million, five hundred eighty-seven thousand, seven hundred twenty-one".