99943890 has 16 divisors (see below), whose sum is σ = 239865408. Its totient is φ = 26651696.

The previous prime is 99943873. The next prime is 99943897. The reversal of 99943890 is 9834999.

It is a super-2 number, since 2×99943890² = 19977562296664200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (99943897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1665702 + ... + 1665761.

It is an arithmetic number, because the mean of its divisors is an integer number (14991588).

Almost surely, 2^99943890 is an apocalyptic number.

99943890 is an abundant number, since it is smaller than the sum of its proper divisors (139921518).

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

99943890 is a wasteful number, since it uses less digits than its factorization.

99943890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3331473.

The product of its (nonzero) digits is 629856, while the sum is 51.

The square root of 99943890 is about 9997.1941063480. The cubic root of 99943890 is about 464.0720539361.

The spelling of 99943890 in words is "ninety-nine million, nine hundred forty-three thousand, eight hundred ninety".