924181981 has 2 divisors, whose sum is σ = 924181982. Its totient is φ = 924181980.

The previous prime is 924181961. The next prime is 924182003. The reversal of 924181981 is 189181429.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 922093956 + 2088025 = 30366^2 + 1445^2 .

It is an emirp because it is prime and its reverse (189181429) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 924181981 - 2¹⁷ = 924050909 is a prime.

It is a super-2 number, since 2×924181981² = 1708224668010168722, which contains 22 as substring.

It is equal to p_47181994 and since 924181981 and 47181994 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (924181901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 462090990 + 462090991.

It is an arithmetic number, because the mean of its divisors is an integer number (462090991).

Almost surely, 2^924181981 is an apocalyptic number.

It is an amenable number.

924181981 is a deficient number, since it is larger than the sum of its proper divisors (1).

924181981 is an equidigital number, since it uses as much as digits as its factorization.

924181981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 43.

The square root of 924181981 is about 30400.3615274556. The cubic root of 924181981 is about 974.0602757189.

The spelling of 924181981 in words is "nine hundred twenty-four million, one hundred eighty-one thousand, nine hundred eighty-one".