69906321 has 15 divisors (see below), whose sum is σ = 104540491.
Its totient is φ = 46554048.
The previous prime is 69906307. The next prime is 69906323. The reversal of 69906321 is 12360996.
Multipling 69906321 by its sum of digits (36), we get a square (2516627556 = 501662).
The square root of 69906321 is 8361.
It is a perfect power (a square), and thus also a powerful number.
It can be written as a sum of positive squares in only one way, i.e., 1347921 + 68558400 = 1161^2 + 8280^2
It is not a de Polignac number, because 69906321 - 25 = 69906289 is a prime.
It is a super-4 number, since 4×699063214 (a number of 32 digits) contains 4444 as substring.
It is a Duffinian number.
It is a Curzon number.
It is not an unprimeable number, because it can be changed into a prime (69906323) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (13) of ones.
It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 74785 + ... + 75713.
Almost surely, 269906321 is an apocalyptic number.
69906321 is the 8361-st square number.
69906321 is the 4181-st centered octagonal number.
It is an amenable number.
69906321 is a deficient number, since it is larger than the sum of its proper divisors (34634170).
69906321 is an frugal number, since it uses more digits than its factorization.
69906321 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1870 (or 932 counting only the distinct ones).
The product of its (nonzero) digits is 17496, while the sum is 36.
The cubic root of 69906321 is about 411.9446012954.
The spelling of 69906321 in words is "sixty-nine million, nine hundred six thousand, three hundred twenty-one".