920423821 has 16 divisors (see below), whose sum is σ = 1043619840. Its totient is φ = 807150960.

The previous prime is 920423813. The next prime is 920423827. The reversal of 920423821 is 128324029.

It is not a de Polignac number, because 920423821 - 2³ = 920423813 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (920423827) 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 15 ways as a sum of consecutive naturals, for example, 20425 + ... + 47518.

It is an arithmetic number, because the mean of its divisors is an integer number (65226240).

Almost surely, 2^920423821 is an apocalyptic number.

It is an amenable number.

920423821 is a deficient number, since it is larger than the sum of its proper divisors (123196019).

920423821 is a wasteful number, since it uses less digits than its factorization.

920423821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68016.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 920423821 is about 30338.4874540574. The cubic root of 920423821 is about 972.7381524101.

The spelling of 920423821 in words is "nine hundred twenty million, four hundred twenty-three thousand, eight hundred twenty-one".