999961558 has 4 divisors (see below), whose sum is σ = 1499942340. Its totient is φ = 499980778.

The previous prime is 999961541. The next prime is 999961577. The reversal of 999961558 is 855169999.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 999961496 and 999961505.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249990388 + ... + 249990391.

It is an arithmetic number, because the mean of its divisors is an integer number (374985585).

Almost surely, 2^999961558 is an apocalyptic number.

999961558 is a deficient number, since it is larger than the sum of its proper divisors (499980782).

999961558 is a wasteful number, since it uses less digits than its factorization.

999961558 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499980781.

The product of its digits is 7873200, while the sum is 61.

The square root of 999961558 is about 31622.1687744532. The cubic root of 999961558 is about 999.9871858358.

The spelling of 999961558 in words is "nine hundred ninety-nine million, nine hundred sixty-one thousand, five hundred fifty-eight".