7842774521 has 4 divisors (see below), whose sum is σ = 8009642112. Its totient is φ = 7675906932.

The previous prime is 7842774487. The next prime is 7842774539. The reversal of 7842774521 is 1254772487.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7842774521 is a prime.

It is a super-2 number, since 2×7842774521² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47), and also a Moran number because the ratio is a prime number: 166867543 = 7842774521 / (7 + 8 + 4 + 2 + 7 + 7 + 4 + 5 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7842770521) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 83433725 + ... + 83433818.

It is an arithmetic number, because the mean of its divisors is an integer number (2002410528).

Almost surely, 2^7842774521 is an apocalyptic number.

It is an amenable number.

7842774521 is a deficient number, since it is larger than the sum of its proper divisors (166867591).

7842774521 is a wasteful number, since it uses less digits than its factorization.

7842774521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166867590.

The product of its digits is 878080, while the sum is 47.

The square root of 7842774521 is about 88559.4406091186. The cubic root of 7842774521 is about 1986.8110943145.

The spelling of 7842774521 in words is "seven billion, eight hundred forty-two million, seven hundred seventy-four thousand, five hundred twenty-one".