501389881 has 2 divisors, whose sum is σ = 501389882. Its totient is φ = 501389880.

The previous prime is 501389873. The next prime is 501389899. The reversal of 501389881 is 188983105.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 475937856 + 25452025 = 21816^2 + 5045^2 .

It is a cyclic number.

It is not a de Polignac number, because 501389881 - 2³ = 501389873 is a prime.

It is a super-2 number, since 2×501389881² = 502783625538388322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (501389821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250694940 + 250694941.

It is an arithmetic number, because the mean of its divisors is an integer number (250694941).

Almost surely, 2^501389881 is an apocalyptic number.

It is an amenable number.

501389881 is a deficient number, since it is larger than the sum of its proper divisors (1).

501389881 is an equidigital number, since it uses as much as digits as its factorization.

501389881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 43.

The square root of 501389881 is about 22391.7368910944. The cubic root of 501389881 is about 794.4352784456.

The spelling of 501389881 in words is "five hundred one million, three hundred eighty-nine thousand, eight hundred eighty-one".