65471921 has 4 divisors (see below), whose sum is σ = 65489700. Its totient is φ = 65454144.

The previous prime is 65471911. The next prime is 65471951. The reversal of 65471921 is 12917456.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 64625521 + 846400 = 8039^2 + 920^2 .

It is a cyclic number.

It is not a de Polignac number, because 65471921 - 2²² = 61277617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65471911) 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, 1076 + ... + 11493.

It is an arithmetic number, because the mean of its divisors is an integer number (16372425).

Almost surely, 2^65471921 is an apocalyptic number.

It is an amenable number.

65471921 is a deficient number, since it is larger than the sum of its proper divisors (17779).

65471921 is a wasteful number, since it uses less digits than its factorization.

65471921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17778.

The product of its digits is 15120, while the sum is 35.

The square root of 65471921 is about 8091.4721157525. The cubic root of 65471921 is about 403.0432893380.

The spelling of 65471921 in words is "sixty-five million, four hundred seventy-one thousand, nine hundred twenty-one".