521632987 has 2 divisors, whose sum is σ = 521632988. Its totient is φ = 521632986.

The previous prime is 521632921. The next prime is 521632997. The reversal of 521632987 is 789236125.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521632987 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (521632997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260816493 + 260816494.

It is an arithmetic number, because the mean of its divisors is an integer number (260816494).

Almost surely, 2^521632987 is an apocalyptic number.

521632987 is a deficient number, since it is larger than the sum of its proper divisors (1).

521632987 is an equidigital number, since it uses as much as digits as its factorization.

521632987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 43.

The square root of 521632987 is about 22839.2860440076. The cubic root of 521632987 is about 804.9860404199.

The spelling of 521632987 in words is "five hundred twenty-one million, six hundred thirty-two thousand, nine hundred eighty-seven".