76649861 has 2 divisors, whose sum is σ = 76649862. Its totient is φ = 76649860.

The previous prime is 76649851. The next prime is 76649863. The reversal of 76649861 is 16894667.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73017025 + 3632836 = 8545^2 + 1906^2 .

It is a cyclic number.

It is not a de Polignac number, because 76649861 - 2²⁶ = 9540997 is a prime.

Together with 76649863, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (76649863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38324930 + 38324931.

It is an arithmetic number, because the mean of its divisors is an integer number (38324931).

Almost surely, 2^76649861 is an apocalyptic number.

It is an amenable number.

76649861 is a deficient number, since it is larger than the sum of its proper divisors (1).

76649861 is an equidigital number, since it uses as much as digits as its factorization.

76649861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 47.

The square root of 76649861 is about 8754.9906339185. The cubic root of 76649861 is about 424.7862565348.

The spelling of 76649861 in words is "seventy-six million, six hundred forty-nine thousand, eight hundred sixty-one".