20401523 has 2 divisors, whose sum is σ = 20401524. Its totient is φ = 20401522.

The previous prime is 20401501. The next prime is 20401553. The reversal of 20401523 is 32510402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20401523 - 2¹² = 20397427 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20401553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10200761 + 10200762.

It is an arithmetic number, because the mean of its divisors is an integer number (10200762).

Almost surely, 2^20401523 is an apocalyptic number.

20401523 is a deficient number, since it is larger than the sum of its proper divisors (1).

20401523 is an equidigital number, since it uses as much as digits as its factorization.

20401523 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 20401523 is about 4516.8045120417. The cubic root of 20401523 is about 273.2462411734.

Adding to 20401523 its reverse (32510402), we get a palindrome (52911925).

The spelling of 20401523 in words is "twenty million, four hundred one thousand, five hundred twenty-three".