1200400051 has 4 divisors (see below), whose sum is σ = 1201008600. Its totient is φ = 1199791504.

The previous prime is 1200400037. The next prime is 1200400079. The reversal of 1200400051 is 1500040021.

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

It is a cyclic number.

It is not a de Polignac number, because 1200400051 - 2⁹ = 1200399539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1200400001) 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, 301306 + ... + 305263.

It is an arithmetic number, because the mean of its divisors is an integer number (300252150).

Almost surely, 2^1200400051 is an apocalyptic number.

1200400051 is a deficient number, since it is larger than the sum of its proper divisors (608549).

1200400051 is an equidigital number, since it uses as much as digits as its factorization.

1200400051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608548.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 1200400051 is about 34646.7899090233. The cubic root of 1200400051 is about 1062.7766442911.

Adding to 1200400051 its reverse (1500040021), we get a palindrome (2700440072).

The spelling of 1200400051 in words is "one billion, two hundred million, four hundred thousand, fifty-one".