65993551 has 4 divisors (see below), whose sum is σ = 71069992. Its totient is φ = 60917112.

The previous prime is 65993539. The next prime is 65993561. The reversal of 65993551 is 15539956.

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 65993551 - 2⁷ = 65993423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65993498 and 65993507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65993561) 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, 2538201 + ... + 2538226.

It is an arithmetic number, because the mean of its divisors is an integer number (17767498).

Almost surely, 2^65993551 is an apocalyptic number.

65993551 is a deficient number, since it is larger than the sum of its proper divisors (5076441).

65993551 is a wasteful number, since it uses less digits than its factorization.

65993551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5076440.

The product of its digits is 182250, while the sum is 43.

The square root of 65993551 is about 8123.6414864271. The cubic root of 65993551 is about 404.1108390290.

The spelling of 65993551 in words is "sixty-five million, nine hundred ninety-three thousand, five hundred fifty-one".