18929081 has 2 divisors, whose sum is σ = 18929082. Its totient is φ = 18929080.

The previous prime is 18929077. The next prime is 18929101. The reversal of 18929081 is 18092981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10137856 + 8791225 = 3184^2 + 2965^2 .

It is a cyclic number.

It is not a de Polignac number, because 18929081 - 2² = 18929077 is a prime.

It is a super-2 number, since 2×18929081² = 716620215009122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18929051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9464540 + 9464541.

It is an arithmetic number, because the mean of its divisors is an integer number (9464541).

Almost surely, 2^18929081 is an apocalyptic number.

It is an amenable number.

18929081 is a deficient number, since it is larger than the sum of its proper divisors (1).

18929081 is an equidigital number, since it uses as much as digits as its factorization.

18929081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 38.

The square root of 18929081 is about 4350.7563710233. The cubic root of 18929081 is about 266.5077502800.

The spelling of 18929081 in words is "eighteen million, nine hundred twenty-nine thousand, eighty-one".