501981929 has 2 divisors, whose sum is σ = 501981930. Its totient is φ = 501981928.

The previous prime is 501981911. The next prime is 501981943. The reversal of 501981929 is 929189105.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 391248400 + 110733529 = 19780^2 + 10523^2 .

It is a cyclic number.

It is not a de Polignac number, because 501981929 - 2⁸ = 501981673 is a prime.

It is a super-2 number, since 2×501981929² = 503971714085122082, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 501981929.

It is not a weakly prime, because it can be changed into another prime (501981979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250990964 + 250990965.

It is an arithmetic number, because the mean of its divisors is an integer number (250990965).

Almost surely, 2^501981929 is an apocalyptic number.

It is an amenable number.

501981929 is a deficient number, since it is larger than the sum of its proper divisors (1).

501981929 is an equidigital number, since it uses as much as digits as its factorization.

501981929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 44.

The square root of 501981929 is about 22404.9532246778. The cubic root of 501981929 is about 794.7478487809.

The spelling of 501981929 in words is "five hundred one million, nine hundred eighty-one thousand, nine hundred twenty-nine".