40819945 has 4 divisors (see below), whose sum is σ = 48983940. Its totient is φ = 32655952.

The previous prime is 40819903. The next prime is 40819957. The reversal of 40819945 is 54991804.

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 29041321 + 11778624 = 5389^2 + 3432^2 .

It is a cyclic number.

It is not a de Polignac number, because 40819945 - 2¹⁹ = 40295657 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40819898 and 40819907.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4081990 + ... + 4081999.

It is an arithmetic number, because the mean of its divisors is an integer number (12245985).

Almost surely, 2^40819945 is an apocalyptic number.

It is an amenable number.

40819945 is a deficient number, since it is larger than the sum of its proper divisors (8163995).

40819945 is an equidigital number, since it uses as much as digits as its factorization.

40819945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8163994.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 40819945 is about 6389.0488337467. The cubic root of 40819945 is about 344.3162119690.

It can be divided in two parts, 4081 and 9945, that multiplied together give a triangular number (40585545 = T₉₀₀₉).

The spelling of 40819945 in words is "forty million, eight hundred nineteen thousand, nine hundred forty-five".