999961994 has 4 divisors (see below), whose sum is σ = 1499942994. Its totient is φ = 499980996.

The previous prime is 999961979. The next prime is 999962057. The reversal of 999961994 is 499169999.

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

It can be written as a sum of positive squares in only one way, i.e., 621853969 + 378108025 = 24937^2 + 19445^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 999961994.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249990497 + ... + 249990500.

Almost surely, 2^999961994 is an apocalyptic number.

999961994 is a deficient number, since it is larger than the sum of its proper divisors (499981000).

999961994 is a wasteful number, since it uses less digits than its factorization.

999961994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499980999.

The product of its digits is 12754584, while the sum is 65.

The square root of 999961994 is about 31622.1756683502. The cubic root of 999961994 is about 999.9873311728.

The spelling of 999961994 in words is "nine hundred ninety-nine million, nine hundred sixty-one thousand, nine hundred ninety-four".