990001684 has 18 divisors (see below), whose sum is σ = 2015360970. Its totient is φ = 424286352.

The previous prime is 990001657. The next prime is 990001687. The reversal of 990001684 is 486100099.

It can be written as a sum of positive squares in only one way, i.e., 893412100 + 96589584 = 29890^2 + 9828^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990001687) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2525319 + ... + 2525710.

Almost surely, 2^990001684 is an apocalyptic number.

It is an amenable number.

990001684 is an abundant number, since it is smaller than the sum of its proper divisors (1025359286).

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

990001684 is a wasteful number, since it uses less digits than its factorization.

990001684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5051047 (or 5051038 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 990001684 is about 31464.2922056098. The cubic root of 990001684 is about 996.6560585193.

The spelling of 990001684 in words is "nine hundred ninety million, one thousand, six hundred eighty-four".