20101023 has 24 divisors (see below), whose sum is σ = 29877120. Its totient is φ = 13018320.

The previous prime is 20101013. The next prime is 20101073. The reversal of 20101023 is 32010102.

It is a happy number.

It is not a de Polignac number, because 20101023 - 2⁵ = 20100991 is a prime.

It is a super-2 number, since 2×20101023² = 808102251293058, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 20100996 and 20101014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101013) 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, 52848 + ... + 53226.

It is an arithmetic number, because the mean of its divisors is an integer number (1244880).

Almost surely, 2^20101023 is an apocalyptic number.

20101023 is a deficient number, since it is larger than the sum of its proper divisors (9776097).

20101023 is a wasteful number, since it uses less digits than its factorization.

20101023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539 (or 536 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 20101023 is about 4483.4164428480. The cubic root of 20101023 is about 271.8980253190.

Adding to 20101023 its reverse (32010102), we get a palindrome (52111125).

It can be divided in two parts, 2010102 and 3, that multiplied together give a palindrome (6030306).

The spelling of 20101023 in words is "twenty million, one hundred one thousand, twenty-three".