40021520 has 160 divisors (see below), whose sum is σ = 118920960. Its totient is φ = 12165120.

The previous prime is 40021517. The next prime is 40021547. The reversal of 40021520 is 2512004.

It is a super-2 number, since 2×40021520² = 3203444126220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 40021495 and 40021504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 449636 + ... + 449724.

It is an arithmetic number, because the mean of its divisors is an integer number (743256).

Almost surely, 2^40021520 is an apocalyptic number.

40021520 is a gapful number since it is divisible by the number (40) 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 40021520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59460480).

40021520 is an abundant number, since it is smaller than the sum of its proper divisors (78899440).

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

40021520 is a wasteful number, since it uses less digits than its factorization.

40021520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 40021520 is about 6326.2563969539. The cubic root of 40021520 is about 342.0565094772.

Adding to 40021520 its reverse (2512004), we get a palindrome (42533524).

The spelling of 40021520 in words is "forty million, twenty-one thousand, five hundred twenty".