7842721725 has 36 divisors (see below), whose sum is σ = 14567463456. Its totient is φ = 4182781680.

The previous prime is 7842721717. The next prime is 7842721753. The reversal of 7842721725 is 5271272487.

7842721725 is a `hidden beast` number, since 7 + 8 + 427 + 217 + 2 + 5 = 666.

It is not a de Polignac number, because 7842721725 - 2³ = 7842721717 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 639417 + ... + 651566.

Almost surely, 2^7842721725 is an apocalyptic number.

7842721725 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

7842721725 is a deficient number, since it is larger than the sum of its proper divisors (6724741731).

7842721725 is a wasteful number, since it uses less digits than its factorization.

7842721725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291008 (or 1290991 counting only the distinct ones).

The product of its digits is 439040, while the sum is 45.

The square root of 7842721725 is about 88559.1425263366. The cubic root of 7842721725 is about 1986.8066360320.

The spelling of 7842721725 in words is "seven billion, eight hundred forty-two million, seven hundred twenty-one thousand, seven hundred twenty-five".