65661371 has 4 divisors (see below), whose sum is σ = 65835000. Its totient is φ = 65487744.

The previous prime is 65661341. The next prime is 65661373. The reversal of 65661371 is 17316656.

It is a happy number.

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 65661371 - 2¹⁸ = 65399227 is a prime.

It is a super-2 number, since 2×65661371² = 8622831283199282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65661373) 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, 86246 + ... + 87003.

It is an arithmetic number, because the mean of its divisors is an integer number (16458750).

Almost surely, 2^65661371 is an apocalyptic number.

65661371 is a deficient number, since it is larger than the sum of its proper divisors (173629).

65661371 is a wasteful number, since it uses less digits than its factorization.

65661371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173628.

The product of its digits is 22680, while the sum is 35.

The square root of 65661371 is about 8103.1704289124. The cubic root of 65661371 is about 403.4316645863.

The spelling of 65661371 in words is "sixty-five million, six hundred sixty-one thousand, three hundred seventy-one".