20121623 has 2 divisors, whose sum is σ = 20121624. Its totient is φ = 20121622.

The previous prime is 20121581. The next prime is 20121653. The reversal of 20121623 is 32612102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20121623 - 2⁶ = 20121559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20121653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060811 + 10060812.

It is an arithmetic number, because the mean of its divisors is an integer number (10060812).

Almost surely, 2^20121623 is an apocalyptic number.

20121623 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121623 is an equidigital number, since it uses as much as digits as its factorization.

20121623 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 20121623 is about 4485.7132097360. The cubic root of 20121623 is about 271.9908760997.

Adding to 20121623 its reverse (32612102), we get a palindrome (52733725).

The spelling of 20121623 in words is "twenty million, one hundred twenty-one thousand, six hundred twenty-three".