65881813 has 4 divisors (see below), whose sum is σ = 66715840. Its totient is φ = 65047788.

The previous prime is 65881811. The next prime is 65881841. The reversal of 65881813 is 31818856.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 65881813 - 2¹ = 65881811 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65881811) 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, 416895 + ... + 417052.

It is an arithmetic number, because the mean of its divisors is an integer number (16678960).

Almost surely, 2^65881813 is an apocalyptic number.

It is an amenable number.

65881813 is a deficient number, since it is larger than the sum of its proper divisors (834027).

65881813 is an equidigital number, since it uses as much as digits as its factorization.

65881813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 834026.

The product of its digits is 46080, while the sum is 40.

The square root of 65881813 is about 8116.7612383265. The cubic root of 65881813 is about 403.8826346820.

The spelling of 65881813 in words is "sixty-five million, eight hundred eighty-one thousand, eight hundred thirteen".