21023123002040 has 32 divisors (see below), whose sum is σ = 47563363935360. Its totient is φ = 8362789257600.

The previous prime is 21023123002001. The next prime is 21023123002043. The reversal of 21023123002040 is 4020032132012.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023123002043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1451865896 + ... + 1451880375.

It is an arithmetic number, because the mean of its divisors is an integer number (1486355122980).

Almost surely, 2^{21023123002040} is an apocalyptic number.

21023123002040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21023123002040 is an abundant number, since it is smaller than the sum of its proper divisors (26540240933320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21023123002040 is a wasteful number, since it uses less digits than its factorization.

21023123002040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2903746463 (or 2903746459 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21023123002040 its reverse (4020032132012), we get a palindrome (25043155134052).

The spelling of 21023123002040 in words is "twenty-one trillion, twenty-three billion, one hundred twenty-three million, two thousand, forty".