40645251 has 6 divisors (see below), whose sum is σ = 58709820. Its totient is φ = 27096828.

The previous prime is 40645229. The next prime is 40645261. The reversal of 40645251 is 15254604.

40645251 is a `hidden beast` number, since 406 + 4 + 5 + 251 = 666.

It is not a de Polignac number, because 40645251 - 2¹³ = 40637059 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40645261) 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 5 ways as a sum of consecutive naturals, for example, 2258061 + ... + 2258078.

It is an arithmetic number, because the mean of its divisors is an integer number (9784970).

Almost surely, 2^40645251 is an apocalyptic number.

40645251 is a deficient number, since it is larger than the sum of its proper divisors (18064569).

40645251 is a wasteful number, since it uses less digits than its factorization.

40645251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4516145 (or 4516142 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 40645251 is about 6375.3628132052. The cubic root of 40645251 is about 343.8243283457.

Adding to 40645251 its reverse (15254604), we get a palindrome (55899855).

The spelling of 40645251 in words is "forty million, six hundred forty-five thousand, two hundred fifty-one".