40521921 has 16 divisors (see below), whose sum is σ = 59162880. Its totient is φ = 24466320.

The previous prime is 40521911. The next prime is 40521937. The reversal of 40521921 is 12912504.

It is not a de Polignac number, because 40521921 - 2¹³ = 40513729 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40521891 and 40521900.

It is not an unprimeable number, because it can be changed into a prime (40521911) 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, 7170 + ... + 11508.

It is an arithmetic number, because the mean of its divisors is an integer number (3697680).

Almost surely, 2^40521921 is an apocalyptic number.

It is an amenable number.

40521921 is a deficient number, since it is larger than the sum of its proper divisors (18640959).

40521921 is a wasteful number, since it uses less digits than its factorization.

40521921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4636.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 40521921 is about 6365.6830741092. The cubic root of 40521921 is about 343.4762203091.

The spelling of 40521921 in words is "forty million, five hundred twenty-one thousand, nine hundred twenty-one".