388744981 has 2 divisors, whose sum is σ = 388744982. Its totient is φ = 388744980.

The previous prime is 388744949. The next prime is 388745003. The reversal of 388744981 is 189447883.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 351900081 + 36844900 = 18759^2 + 6070^2 .

It is a cyclic number.

It is not a de Polignac number, because 388744981 - 2⁵ = 388744949 is a prime.

It is a super-2 number, since 2×388744981² = 302245320505380722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (388748981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194372490 + 194372491.

It is an arithmetic number, because the mean of its divisors is an integer number (194372491).

Almost surely, 2^388744981 is an apocalyptic number.

It is an amenable number.

388744981 is a deficient number, since it is larger than the sum of its proper divisors (1).

388744981 is an equidigital number, since it uses as much as digits as its factorization.

388744981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1548288, while the sum is 52.

The square root of 388744981 is about 19716.6168751132. The cubic root of 388744981 is about 729.8298102036.

The spelling of 388744981 in words is "three hundred eighty-eight million, seven hundred forty-four thousand, nine hundred eighty-one".