9999551 has 8 divisors (see below), whose sum is σ = 10164000. Its totient is φ = 9836640.

The previous prime is 9999533. The next prime is 9999593. The reversal of 9999551 is 1559999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9999551 - 2¹⁸ = 9737407 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 9999496 and 9999505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999511) 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 7 ways as a sum of consecutive naturals, for example, 21461 + ... + 21921.

It is an arithmetic number, because the mean of its divisors is an integer number (1270500).

Almost surely, 2^9999551 is an apocalyptic number.

9999551 is a deficient number, since it is larger than the sum of its proper divisors (164449).

9999551 is a wasteful number, since it uses less digits than its factorization.

9999551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 769.

The product of its digits is 164025, while the sum is 47.

The square root of 9999551 is about 3162.2066662380. The cubic root of 9999551 is about 215.4402444843.

The spelling of 9999551 in words is "nine million, nine hundred ninety-nine thousand, five hundred fifty-one".