87777649 has 2 divisors, whose sum is σ = 87777650. Its totient is φ = 87777648.

The previous prime is 87777629. The next prime is 87777671. The reversal of 87777649 is 94677778.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87759424 + 18225 = 9368^2 + 135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87777649 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87777649.

It is not a weakly prime, because it can be changed into another prime (87777629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43888824 + 43888825.

It is an arithmetic number, because the mean of its divisors is an integer number (43888825).

Almost surely, 2^87777649 is an apocalyptic number.

It is an amenable number.

87777649 is a deficient number, since it is larger than the sum of its proper divisors (1).

87777649 is an equidigital number, since it uses as much as digits as its factorization.

87777649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4148928, while the sum is 55.

The square root of 87777649 is about 9368.9726758060. The cubic root of 87777649 is about 444.4210777553.

The spelling of 87777649 in words is "eighty-seven million, seven hundred seventy-seven thousand, six hundred forty-nine".