990990145 has 8 divisors (see below), whose sum is σ = 1191839400. Its totient is φ = 791024640.

The previous prime is 990990127. The next prime is 990990149. The reversal of 990990145 is 541099099.

It can be written as a sum of positive squares in 4 ways, for example, as 185395456 + 805594689 = 13616^2 + 28383^2 .

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

It is not a de Polignac number, because 990990145 - 2²⁷ = 856772417 is a prime.

It is a super-2 number, since 2×990990145² = 1964122934974242050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 990990095 and 990990104.

It is not an unprimeable number, because it can be changed into a prime (990990149) 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, 218466 + ... + 222955.

It is an arithmetic number, because the mean of its divisors is an integer number (148979925).

Almost surely, 2^990990145 is an apocalyptic number.

It is an amenable number.

990990145 is a deficient number, since it is larger than the sum of its proper divisors (200849255).

990990145 is a wasteful number, since it uses less digits than its factorization.

990990145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441875.

The product of its (nonzero) digits is 131220, while the sum is 46.

The square root of 990990145 is about 31479.9959498091. The cubic root of 990990145 is about 996.9876498582.

The spelling of 990990145 in words is "nine hundred ninety million, nine hundred ninety thousand, one hundred forty-five".