20100221523 has 24 divisors (see below), whose sum is σ = 31147225200. Its totient is φ = 12938069088.

The previous prime is 20100221521. The next prime is 20100221527. The reversal of 20100221523 is 32512200102.

20100221523 is a `hidden beast` number, since 20 + 100 + 2 + 21 + 523 = 666.

It is not a de Polignac number, because 20100221523 - 2¹ = 20100221521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20100221496 and 20100221505.

It is not an unprimeable number, because it can be changed into a prime (20100221521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1419108 + ... + 1433201.

It is an arithmetic number, because the mean of its divisors is an integer number (1297801050).

Almost surely, 2^20100221523 is an apocalyptic number.

20100221523 is a deficient number, since it is larger than the sum of its proper divisors (11047003677).

20100221523 is an equidigital number, since it uses as much as digits as its factorization.

20100221523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2852353 (or 2852341 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

Adding to 20100221523 its reverse (32512200102), we get a palindrome (52612421625).

The spelling of 20100221523 in words is "twenty billion, one hundred million, two hundred twenty-one thousand, five hundred twenty-three".