400071538 has 4 divisors (see below), whose sum is σ = 600107310. Its totient is φ = 200035768.

The previous prime is 400071533. The next prime is 400071541. The reversal of 400071538 is 835170004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 393347889 + 6723649 = 19833^2 + 2593^2 .

It is not an unprimeable number, because it can be changed into a prime (400071533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100017883 + ... + 100017886.

Almost surely, 2^400071538 is an apocalyptic number.

400071538 is a deficient number, since it is larger than the sum of its proper divisors (200035772).

400071538 is a wasteful number, since it uses less digits than its factorization.

400071538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200035771.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 400071538 is about 20001.7883700433. The cubic root of 400071538 is about 736.8502218173.

The spelling of 400071538 in words is "four hundred million, seventy-one thousand, five hundred thirty-eight".