400044551 has 4 divisors (see below), whose sum is σ = 402075432. Its totient is φ = 398013672.

The previous prime is 400044529. The next prime is 400044581. The reversal of 400044551 is 155440004.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400044551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400044511) 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, 1015145 + ... + 1015538.

It is an arithmetic number, because the mean of its divisors is an integer number (100518858).

Almost surely, 2^400044551 is an apocalyptic number.

400044551 is a deficient number, since it is larger than the sum of its proper divisors (2030881).

400044551 is a wasteful number, since it uses less digits than its factorization.

400044551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2030880.

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 400044551 is about 20001.1137439894. The cubic root of 400044551 is about 736.8336532605.

Adding to 400044551 its reverse (155440004), we get a palindrome (555484555).

The spelling of 400044551 in words is "four hundred million, forty-four thousand, five hundred fifty-one".