40161555 has 32 divisors (see below), whose sum is σ = 81600000. Its totient is φ = 18359136.

The previous prime is 40161553. The next prime is 40161557. The reversal of 40161555 is 55516104.

It is a happy number.

40161555 is a `hidden beast` number, since 40 + 1 + 615 + 5 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (40161553) and next prime (40161557).

It is not a de Polignac number, because 40161555 - 2¹ = 40161553 is a prime.

It is a super-2 number, since 2×40161555² = 3225901000036050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (40161551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20305 + ... + 22194.

It is an arithmetic number, because the mean of its divisors is an integer number (2550000).

Almost surely, 2^40161555 is an apocalyptic number.

40161555 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

40161555 is an abundant number, since it is smaller than the sum of its proper divisors (41438445).

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

40161555 is a wasteful number, since it uses less digits than its factorization.

40161555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42520 (or 42514 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The square root of 40161555 is about 6337.3144943264. The cubic root of 40161555 is about 342.4549961292.

Adding to 40161555 its reverse (55516104), we get a palindrome (95677659).

The spelling of 40161555 in words is "forty million, one hundred sixty-one thousand, five hundred fifty-five".