69921109477 has 4 divisors (see below), whose sum is σ = 69921663340. Its totient is φ = 69920555616.

The previous prime is 69921109471. The next prime is 69921109519. The reversal of 69921109477 is 77490112996.

It is a Cunningham number, because it is equal to 264426²+1.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 65943158436 + 3977951041 = 256794^2 + 63071^2 .

It is a cyclic number.

It is not a de Polignac number, because 69921109477 - 2¹¹ = 69921107429 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 (69921109471) 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, 15049 + ... + 374257.

It is an arithmetic number, because the mean of its divisors is an integer number (17480415835).

Almost surely, 2^69921109477 is an apocalyptic number.

It is an amenable number.

69921109477 is a deficient number, since it is larger than the sum of its proper divisors (553863).

69921109477 is a wasteful number, since it uses less digits than its factorization.

69921109477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553862.

The product of its (nonzero) digits is 1714608, while the sum is 55.

The spelling of 69921109477 in words is "sixty-nine billion, nine hundred twenty-one million, one hundred nine thousand, four hundred seventy-seven".