63509491 has 4 divisors (see below), whose sum is σ = 64126192. Its totient is φ = 62892792.

The previous prime is 63509477. The next prime is 63509513. The reversal of 63509491 is 19490536.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 63509491 - 2¹⁵ = 63476723 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63509491.

It is not an unprimeable number, because it can be changed into a prime (63509401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 308196 + ... + 308401.

It is an arithmetic number, because the mean of its divisors is an integer number (16031548).

Almost surely, 2^63509491 is an apocalyptic number.

63509491 is a deficient number, since it is larger than the sum of its proper divisors (616701).

63509491 is a wasteful number, since it uses less digits than its factorization.

63509491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 616700.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 63509491 is about 7969.2842213087. The cubic root of 63509491 is about 398.9754844099.

It can be divided in two parts, 63509 and 491, that added together give a cube (64000 = 40³).

The spelling of 63509491 in words is "sixty-three million, five hundred nine thousand, four hundred ninety-one".