7721985745 has 8 divisors (see below), whose sum is σ = 9383679360. Its totient is φ = 6099390960.

The previous prime is 7721985727. The next prime is 7721985763. The reversal of 7721985745 is 5475891277.

It is an interprime number because it is at equal distance from previous prime (7721985727) and next prime (7721985763).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 7721985745 - 2⁷ = 7721985617 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9774271 + ... + 9775060.

It is an arithmetic number, because the mean of its divisors is an integer number (1172959920).

Almost surely, 2^7721985745 is an apocalyptic number.

It is an amenable number.

7721985745 is a deficient number, since it is larger than the sum of its proper divisors (1661693615).

7721985745 is a wasteful number, since it uses less digits than its factorization.

7721985745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19549415.

The product of its digits is 4939200, while the sum is 55.

The square root of 7721985745 is about 87874.8299856108. The cubic root of 7721985745 is about 1976.5584660985.

The spelling of 7721985745 in words is "seven billion, seven hundred twenty-one million, nine hundred eighty-five thousand, seven hundred forty-five".