40293781 has 4 divisors (see below), whose sum is σ = 43956864. Its totient is φ = 36630700.

The previous prime is 40293697. The next prime is 40293809. The reversal of 40293781 is 18739204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40293781 - 2¹³ = 40285589 is a prime.

It is a super-2 number, since 2×40293781² = 3247177574551922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40293581) 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, 1831525 + ... + 1831546.

It is an arithmetic number, because the mean of its divisors is an integer number (10989216).

Almost surely, 2^40293781 is an apocalyptic number.

It is an amenable number.

40293781 is a deficient number, since it is larger than the sum of its proper divisors (3663083).

40293781 is a wasteful number, since it uses less digits than its factorization.

40293781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3663082.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 40293781 is about 6347.7382586241. The cubic root of 40293781 is about 342.8304119619.

The spelling of 40293781 in words is "forty million, two hundred ninety-three thousand, seven hundred eighty-one".