40391040 has 128 divisors (see below), whose sum is σ = 130600800. Its totient is φ = 10616832.

The previous prime is 40391003. The next prime is 40391053. The reversal of 40391040 is 4019304.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×40391040² = 3262872224563200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 40390998 and 40391016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209184 + ... + 209376.

Almost surely, 2^40391040 is an apocalyptic number.

40391040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40391040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65300400).

40391040 is an abundant number, since it is smaller than the sum of its proper divisors (90209760).

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

40391040 is a wasteful number, since it uses less digits than its factorization.

40391040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 40391040 is about 6355.3945589554. The cubic root of 40391040 is about 343.1060256395.

The spelling of 40391040 in words is "forty million, three hundred ninety-one thousand, forty".