65801621 has 4 divisors (see below), whose sum is σ = 66319872. Its totient is φ = 65283372.

The previous prime is 65801587. The next prime is 65801629. The reversal of 65801621 is 12610856.

It is a happy number.

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 65801621 - 2¹⁰ = 65800597 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 (65801629) 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, 258935 + ... + 259188.

It is an arithmetic number, because the mean of its divisors is an integer number (16579968).

Almost surely, 2^65801621 is an apocalyptic number.

It is an amenable number.

65801621 is a deficient number, since it is larger than the sum of its proper divisors (518251).

65801621 is a wasteful number, since it uses less digits than its factorization.

65801621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518250.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 65801621 is about 8111.8198328119. The cubic root of 65801621 is about 403.7186981583.

The spelling of 65801621 in words is "sixty-five million, eight hundred one thousand, six hundred twenty-one".