38777978881 has 2 divisors, whose sum is σ = 38777978882. Its totient is φ = 38777978880.

The previous prime is 38777978879. The next prime is 38777978903. The reversal of 38777978881 is 18887977783.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28689584400 + 10088394481 = 169380^2 + 100441^2 .

It is a cyclic number.

It is not a de Polignac number, because 38777978881 - 2¹ = 38777978879 is a prime.

It is a super-2 number, since 2×38777978881² (a number of 22 digits) contains 22 as substring.

Together with 38777978879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (38777978821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19388989440 + 19388989441.

It is an arithmetic number, because the mean of its divisors is an integer number (19388989441).

Almost surely, 2^38777978881 is an apocalyptic number.

It is an amenable number.

38777978881 is a deficient number, since it is larger than the sum of its proper divisors (1).

38777978881 is an equidigital number, since it uses as much as digits as its factorization.

38777978881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 265531392, while the sum is 73.

The spelling of 38777978881 in words is "thirty-eight billion, seven hundred seventy-seven million, nine hundred seventy-eight thousand, eight hundred eighty-one".