16587337380521 has 2 divisors, whose sum is σ = 16587337380522. Its totient is φ = 16587337380520.

The previous prime is 16587337380517. The next prime is 16587337380527. The reversal of 16587337380521 is 12508373378561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15378632833600 + 1208704546921 = 3921560^2 + 1099411^2 .

It is a cyclic number.

It is not a de Polignac number, because 16587337380521 - 2² = 16587337380517 is a prime.

It is a super-2 number, since 2×16587337380521² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16587337380527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8293668690260 + 8293668690261.

It is an arithmetic number, because the mean of its divisors is an integer number (8293668690261).

Almost surely, 2^{16587337380521} is an apocalyptic number.

It is an amenable number.

16587337380521 is a deficient number, since it is larger than the sum of its proper divisors (1).

16587337380521 is an equidigital number, since it uses as much as digits as its factorization.

16587337380521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25401600, while the sum is 59.

The spelling of 16587337380521 in words is "sixteen trillion, five hundred eighty-seven billion, three hundred thirty-seven million, three hundred eighty thousand, five hundred twenty-one".