7561649971 has 2 divisors, whose sum is σ = 7561649972. Its totient is φ = 7561649970.

The previous prime is 7561649969. The next prime is 7561650043. The reversal of 7561649971 is 1799461657.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 7561649971 - 2¹ = 7561649969 is a prime.

Together with 7561649969, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (7561649371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3780824985 + 3780824986.

It is an arithmetic number, because the mean of its divisors is an integer number (3780824986).

Almost surely, 2^7561649971 is an apocalyptic number.

7561649971 is a deficient number, since it is larger than the sum of its proper divisors (1).

7561649971 is an equidigital number, since it uses as much as digits as its factorization.

7561649971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2857680, while the sum is 55.

The square root of 7561649971 is about 86957.7481941661. The cubic root of 7561649971 is about 1962.7825578580.

The spelling of 7561649971 in words is "seven billion, five hundred sixty-one million, six hundred forty-nine thousand, nine hundred seventy-one".