61809493 has 2 divisors, whose sum is σ = 61809494. Its totient is φ = 61809492.

The previous prime is 61809491. The next prime is 61809563. The reversal of 61809493 is 39490816.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54508689 + 7300804 = 7383^2 + 2702^2 .

It is a cyclic number.

It is not a de Polignac number, because 61809493 - 2¹ = 61809491 is a prime.

Together with 61809491, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61809491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30904746 + 30904747.

It is an arithmetic number, because the mean of its divisors is an integer number (30904747).

Almost surely, 2^61809493 is an apocalyptic number.

It is an amenable number.

61809493 is a deficient number, since it is larger than the sum of its proper divisors (1).

61809493 is an equidigital number, since it uses as much as digits as its factorization.

61809493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 61809493 is about 7861.9013603581. The cubic root of 61809493 is about 395.3833654549.

The spelling of 61809493 in words is "sixty-one million, eight hundred nine thousand, four hundred ninety-three".