938978981 has 2 divisors, whose sum is σ = 938978982. Its totient is φ = 938978980.

The previous prime is 938978977. The next prime is 938979011. The reversal of 938978981 is 189879839.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 531302500 + 407676481 = 23050^2 + 20191^2 .

It is a cyclic number.

It is not a de Polignac number, because 938978981 - 2² = 938978977 is a prime.

It is a super-2 number, since 2×938978981² = 1763363053519596722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (938978681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 469489490 + 469489491.

It is an arithmetic number, because the mean of its divisors is an integer number (469489491).

Almost surely, 2^938978981 is an apocalyptic number.

It is an amenable number.

938978981 is a deficient number, since it is larger than the sum of its proper divisors (1).

938978981 is an equidigital number, since it uses as much as digits as its factorization.

938978981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 62.

The square root of 938978981 is about 30642.7639255991. The cubic root of 938978981 is about 979.2313078734.

The spelling of 938978981 in words is "nine hundred thirty-eight million, nine hundred seventy-eight thousand, nine hundred eighty-one".