921898 has 4 divisors (see below), whose sum is σ = 1382850. Its totient is φ = 460948.

The previous prime is 921889. The next prime is 921901. The reversal of 921898 is 898129.

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., 908209 + 13689 = 953^2 + 117^2 .

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

921898 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, 230473 + ... + 230476.

2⁹²¹⁸⁹⁸ is an apocalyptic number.

921898 is a deficient number, since it is larger than the sum of its proper divisors (460952).

921898 is a wasteful number, since it uses less digits than its factorization.

921898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460951.

The product of its digits is 10368, while the sum is 37.

The square root of 921898 is about 960.1551957887. The cubic root of 921898 is about 97.3257197814.

It can be divided in two parts, 9218 and 98, that added together give a triangular number (9316 = T₁₃₆).

The spelling of 921898 in words is "nine hundred twenty-one thousand, eight hundred ninety-eight".