123021057 has 4 divisors (see below), whose sum is σ = 164028080. Its totient is φ = 82014036.

The previous prime is 123021053. The next prime is 123021071. The reversal of 123021057 is 750120321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 123021057 - 2² = 123021053 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123021053) 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, 20503507 + ... + 20503512.

It is an arithmetic number, because the mean of its divisors is an integer number (41007020).

Almost surely, 2^123021057 is an apocalyptic number.

It is an amenable number.

123021057 is a deficient number, since it is larger than the sum of its proper divisors (41007023).

123021057 is an equidigital number, since it uses as much as digits as its factorization.

123021057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41007022.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 123021057 is about 11091.4857886579. The cubic root of 123021057 is about 497.3473612355.

Adding to 123021057 its reverse (750120321), we get a palindrome (873141378).

The spelling of 123021057 in words is "one hundred twenty-three million, twenty-one thousand, fifty-seven".