40720121 has 8 divisors (see below), whose sum is σ = 44507904. Its totient is φ = 37026000.

The previous prime is 40720087. The next prime is 40720129. The reversal of 40720121 is 12102704.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40720121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40720121.

It is not an unprimeable number, because it can be changed into a prime (40720129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22505 + ... + 24246.

It is an arithmetic number, because the mean of its divisors is an integer number (5563488).

Almost surely, 2^40720121 is an apocalyptic number.

It is an amenable number.

40720121 is a deficient number, since it is larger than the sum of its proper divisors (3787783).

40720121 is a wasteful number, since it uses less digits than its factorization.

40720121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46831.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 40720121 is about 6381.2319343525. The cubic root of 40720121 is about 344.0353110724.

Adding to 40720121 its reverse (12102704), we get a palindrome (52822825).

The spelling of 40720121 in words is "forty million, seven hundred twenty thousand, one hundred twenty-one".