1251143664406 has 4 divisors (see below), whose sum is σ = 1876715496612. Its totient is φ = 625571832202.

The previous prime is 1251143664389. The next prime is 1251143664409. The reversal of 1251143664406 is 6044663411521.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251143664409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312785916100 + ... + 312785916103.

It is an arithmetic number, because the mean of its divisors is an integer number (469178874153).

Almost surely, 2^{1251143664406} is an apocalyptic number.

1251143664406 is a deficient number, since it is larger than the sum of its proper divisors (625571832206).

1251143664406 is an equidigital number, since it uses as much as digits as its factorization.

1251143664406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625571832205.

The product of its (nonzero) digits is 414720, while the sum is 43.

The spelling of 1251143664406 in words is "one trillion, two hundred fifty-one billion, one hundred forty-three million, six hundred sixty-four thousand, four hundred six".