40121020 has 48 divisors (see below), whose sum is σ = 89812800. Its totient is φ = 15002624.

The previous prime is 40121009. The next prime is 40121023. The reversal of 40121020 is 2012104.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 40120988 and 40121006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40121023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66681 + ... + 67279.

It is an arithmetic number, because the mean of its divisors is an integer number (1871100).

Almost surely, 2^40121020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40121020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44906400).

40121020 is an abundant number, since it is smaller than the sum of its proper divisors (49691780).

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

40121020 is a wasteful number, since it uses less digits than its factorization.

40121020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 822 (or 820 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 40121020 is about 6334.1155657282. The cubic root of 40121020 is about 342.3397442334.

Adding to 40121020 its reverse (2012104), we get a palindrome (42133124).

The spelling of 40121020 in words is "forty million, one hundred twenty-one thousand, twenty".