77981011 has 2 divisors, whose sum is σ = 77981012. Its totient is φ = 77981010.

The previous prime is 77981003. The next prime is 77981021. The reversal of 77981011 is 11018977.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77981011 - 2³ = 77981003 is a prime.

It is not a weakly prime, because it can be changed into another prime (77981021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38990505 + 38990506.

It is an arithmetic number, because the mean of its divisors is an integer number (38990506).

Almost surely, 2^77981011 is an apocalyptic number.

77981011 is a deficient number, since it is larger than the sum of its proper divisors (1).

77981011 is an equidigital number, since it uses as much as digits as its factorization.

77981011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528, while the sum is 34.

The square root of 77981011 is about 8830.6857604605. The cubic root of 77981011 is about 427.2311929131.

Adding to 77981011 its reverse (11018977), we get a palindrome (88999988).

The spelling of 77981011 in words is "seventy-seven million, nine hundred eighty-one thousand, eleven".