20151040 has 144 divisors (see below), whose sum is σ = 59750208. Its totient is φ = 6340608.

The previous prime is 20151031. The next prime is 20151041. The reversal of 20151040 is 4015102.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 20151040.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20151041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116394 + ... + 116566.

It is an arithmetic number, because the mean of its divisors is an integer number (414932).

Almost surely, 2^20151040 is an apocalyptic number.

20151040 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 20151040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29875104).

20151040 is an abundant number, since it is smaller than the sum of its proper divisors (39599168).

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

20151040 is a wasteful number, since it uses less digits than its factorization.

20151040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 200 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 20151040 is about 4488.9909779370. The cubic root of 20151040 is about 272.1233581174.

Adding to 20151040 its reverse (4015102), we get a palindrome (24166142).

The spelling of 20151040 in words is "twenty million, one hundred fifty-one thousand, forty".