521073881 has 2 divisors, whose sum is σ = 521073882. Its totient is φ = 521073880.

The previous prime is 521073869. The next prime is 521073911. The reversal of 521073881 is 188370125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 436433881 + 84640000 = 20891^2 + 9200^2 .

It is a cyclic number.

It is not a de Polignac number, because 521073881 - 2¹⁰ = 521072857 is a prime.

It is a super-2 number, since 2×521073881² = 543035978920804322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_27406079 and since 521073881 and 27406079 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (521073811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260536940 + 260536941.

It is an arithmetic number, because the mean of its divisors is an integer number (260536941).

Almost surely, 2^521073881 is an apocalyptic number.

It is an amenable number.

521073881 is a deficient number, since it is larger than the sum of its proper divisors (1).

521073881 is an equidigital number, since it uses as much as digits as its factorization.

521073881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13440, while the sum is 35.

The square root of 521073881 is about 22827.0427563449. The cubic root of 521073881 is about 804.6983327572.

The spelling of 521073881 in words is "five hundred twenty-one million, seventy-three thousand, eight hundred eighty-one".