40820155 has 4 divisors (see below), whose sum is σ = 48984192. Its totient is φ = 32656120.

The previous prime is 40820141. The next prime is 40820159. The reversal of 40820155 is 55102804.

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

It is not a de Polignac number, because 40820155 - 2¹⁵ = 40787387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40820159) 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, 4082011 + ... + 4082020.

It is an arithmetic number, because the mean of its divisors is an integer number (12246048).

Almost surely, 2^40820155 is an apocalyptic number.

40820155 is a deficient number, since it is larger than the sum of its proper divisors (8164037).

40820155 is an equidigital number, since it uses as much as digits as its factorization.

40820155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8164036.

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 40820155 is about 6389.0652680967. The cubic root of 40820155 is about 344.3168024180.

Subtracting from 40820155 its sum of digits (25), we obtain a triangular number (40820130 = T₉₀₃₅).

Adding to 40820155 its reverse (55102804), we get a palindrome (95922959).

The spelling of 40820155 in words is "forty million, eight hundred twenty thousand, one hundred fifty-five".