9899742 has 32 divisors (see below), whose sum is σ = 20337408. Its totient is φ = 3211776.

The previous prime is 9899731. The next prime is 9899753. The reversal of 9899742 is 2479989.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (9899731) and next prime (9899753).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 9899691 and 9899700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 51198 + ... + 51390.

It is an arithmetic number, because the mean of its divisors is an integer number (635544).

Almost surely, 2^9899742 is an apocalyptic number.

9899742 is an abundant number, since it is smaller than the sum of its proper divisors (10437666).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9899742 is a wasteful number, since it uses less digits than its factorization.

9899742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384.

The product of its digits is 326592, while the sum is 48.

The square root of 9899742 is about 3146.3855453520. The cubic root of 9899742 is about 214.7210516159.

It can be divided in two parts, 989 and 9742, that added together give a triangular number (10731 = T₁₄₆).

The spelling of 9899742 in words is "nine million, eight hundred ninety-nine thousand, seven hundred forty-two".