21040120140 has 192 divisors, whose sum is σ = 64202544000. Its totient is φ = 5117607936.

The previous prime is 21040120139. The next prime is 21040120141. The reversal of 21040120140 is 4102104012.

It is an interprime number because it is at equal distance from previous prime (21040120139) and next prime (21040120141).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (21040120141) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 31262844 + ... + 31263516.

It is an arithmetic number, because the mean of its divisors is an integer number (334388250).

Almost surely, 2^21040120140 is an apocalyptic number.

21040120140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21040120140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32101272000).

21040120140 is an abundant number, since it is smaller than the sum of its proper divisors (43162423860).

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

21040120140 is a wasteful number, since it uses less digits than its factorization.

21040120140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116 (or 1114 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21040120140 its reverse (4102104012), we get a palindrome (25142224152).

The spelling of 21040120140 in words is "twenty-one billion, forty million, one hundred twenty thousand, one hundred forty".