899978 has 4 divisors (see below), whose sum is σ = 1349970. Its totient is φ = 449988.

The previous prime is 899971. The next prime is 899981. The reversal of 899978 is 879998.

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., 494209 + 405769 = 703^2 + 637^2 .

It is not an unprimeable number, because it can be changed into a prime (899971) by changing a digit.

899978 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 224993 + ... + 224996.

2⁸⁹⁹⁹⁷⁸ is an apocalyptic number.

899978 is a deficient number, since it is larger than the sum of its proper divisors (449992).

899978 is a wasteful number, since it uses less digits than its factorization.

899978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449991.

The product of its digits is 326592, while the sum is 50.

The square root of 899978 is about 948.6717029616. The cubic root of 899978 is about 96.5481517591.

The spelling of 899978 in words is "eight hundred ninety-nine thousand, nine hundred seventy-eight".