672521491 has 2 divisors, whose sum is σ = 672521492. Its totient is φ = 672521490.

The previous prime is 672521489. The next prime is 672521519. The reversal of 672521491 is 194125276.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 672521491 - 2¹ = 672521489 is a prime.

Together with 672521489, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 672521491.

It is not a weakly prime, because it can be changed into another prime (672521461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336260745 + 336260746.

It is an arithmetic number, because the mean of its divisors is an integer number (336260746).

Almost surely, 2^672521491 is an apocalyptic number.

672521491 is a deficient number, since it is larger than the sum of its proper divisors (1).

672521491 is an equidigital number, since it uses as much as digits as its factorization.

672521491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 37.

The square root of 672521491 is about 25933.0193190072. The cubic root of 672521491 is about 876.1303447717.

The spelling of 672521491 in words is "six hundred seventy-two million, five hundred twenty-one thousand, four hundred ninety-one".