40978121 has 4 divisors (see below), whose sum is σ = 40998852. Its totient is φ = 40957392.

The previous prime is 40978087. The next prime is 40978123. The reversal of 40978121 is 12187904.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 29822521 + 11155600 = 5461^2 + 3340^2 .

It is a cyclic number.

It is not a de Polignac number, because 40978121 - 2⁶ = 40978057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (40978123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7046 + ... + 11471.

It is an arithmetic number, because the mean of its divisors is an integer number (10249713).

Almost surely, 2^40978121 is an apocalyptic number.

It is an amenable number.

40978121 is a deficient number, since it is larger than the sum of its proper divisors (20731).

40978121 is a wasteful number, since it uses less digits than its factorization.

40978121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20730.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 40978121 is about 6401.4155465803. The cubic root of 40978121 is about 344.7603769092.

The spelling of 40978121 in words is "forty million, nine hundred seventy-eight thousand, one hundred twenty-one".