85423021 has 4 divisors (see below), whose sum is σ = 85696252. Its totient is φ = 85149792.

The previous prime is 85423007. The next prime is 85423027. The reversal of 85423021 is 12032458.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12032458 = 2 ⋅6016229.

It can be written as a sum of positive squares in 2 ways, for example, as 11634921 + 73788100 = 3411^2 + 8590^2 .

It is a cyclic number.

It is not a de Polignac number, because 85423021 - 2¹³ = 85414829 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 (85423027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136146 + ... + 136771.

It is an arithmetic number, because the mean of its divisors is an integer number (21424063).

Almost surely, 2^85423021 is an apocalyptic number.

It is an amenable number.

85423021 is a deficient number, since it is larger than the sum of its proper divisors (273231).

85423021 is a wasteful number, since it uses less digits than its factorization.

85423021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273230.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 85423021 is about 9242.4575195129. The cubic root of 85423021 is about 440.4111532171.

Adding to 85423021 its reverse (12032458), we get a palindrome (97455479).

The spelling of 85423021 in words is "eighty-five million, four hundred twenty-three thousand, twenty-one".