69665921 has 4 divisors (see below), whose sum is σ = 75024852. Its totient is φ = 64306992.

The previous prime is 69665899. The next prime is 69665923. The reversal of 69665921 is 12956696.

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 11296321 + 58369600 = 3361^2 + 7640^2 .

It is a cyclic number.

It is not a de Polignac number, because 69665921 - 2¹⁰ = 69664897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (69665923) 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, 2679446 + ... + 2679471.

It is an arithmetic number, because the mean of its divisors is an integer number (18756213).

Almost surely, 2^69665921 is an apocalyptic number.

It is an amenable number.

69665921 is a deficient number, since it is larger than the sum of its proper divisors (5358931).

69665921 is a wasteful number, since it uses less digits than its factorization.

69665921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5358930.

The product of its digits is 174960, while the sum is 44.

The square root of 69665921 is about 8346.6113483257. The cubic root of 69665921 is about 411.4718485338.

The spelling of 69665921 in words is "sixty-nine million, six hundred sixty-five thousand, nine hundred twenty-one".