77821153 has 2 divisors, whose sum is σ = 77821154. Its totient is φ = 77821152.

The previous prime is 77821151. The next prime is 77821171. The reversal of 77821153 is 35112877.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53100369 + 24720784 = 7287^2 + 4972^2 .

It is an emirp because it is prime and its reverse (35112877) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77821153 - 2¹ = 77821151 is a prime.

It is a super-2 number, since 2×77821153² = 12112263708498818, which contains 22 as substring.

Together with 77821151, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (77821151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38910576 + 38910577.

It is an arithmetic number, because the mean of its divisors is an integer number (38910577).

Almost surely, 2^77821153 is an apocalyptic number.

It is an amenable number.

77821153 is a deficient number, since it is larger than the sum of its proper divisors (1).

77821153 is an equidigital number, since it uses as much as digits as its factorization.

77821153 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11760, while the sum is 34.

The square root of 77821153 is about 8821.6298380741. The cubic root of 77821153 is about 426.9390574961.

The spelling of 77821153 in words is "seventy-seven million, eight hundred twenty-one thousand, one hundred fifty-three".