857992421 has 8 divisors (see below), whose sum is σ = 1007991264. Its totient is φ = 719993520.

The previous prime is 857992411. The next prime is 857992423. The reversal of 857992421 is 124299758.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857992421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857992423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2999831 + ... + 3000116.

It is an arithmetic number, because the mean of its divisors is an integer number (125998908).

Almost surely, 2^857992421 is an apocalyptic number.

It is an amenable number.

857992421 is a deficient number, since it is larger than the sum of its proper divisors (149998843).

857992421 is a wasteful number, since it uses less digits than its factorization.

857992421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5999971.

The product of its digits is 362880, while the sum is 47.

The square root of 857992421 is about 29291.5076600710. The cubic root of 857992421 is about 950.2279862794.

The spelling of 857992421 in words is "eight hundred fifty-seven million, nine hundred ninety-two thousand, four hundred twenty-one".