1251402420351 has 4 divisors (see below), whose sum is σ = 1668536560472. Its totient is φ = 834268280232.

The previous prime is 1251402420349. The next prime is 1251402420379. The reversal of 1251402420351 is 1530242041521.

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

It is not a de Polignac number, because 1251402420351 - 2¹ = 1251402420349 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 (1251402420391) 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, 208567070056 + ... + 208567070061.

It is an arithmetic number, because the mean of its divisors is an integer number (417134140118).

Almost surely, 2^{1251402420351} is an apocalyptic number.

1251402420351 is a deficient number, since it is larger than the sum of its proper divisors (417134140121).

1251402420351 is an equidigital number, since it uses as much as digits as its factorization.

1251402420351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417134140120.

The product of its (nonzero) digits is 9600, while the sum is 30.

Adding to 1251402420351 its reverse (1530242041521), we get a palindrome (2781644461872).

The spelling of 1251402420351 in words is "one trillion, two hundred fifty-one billion, four hundred two million, four hundred twenty thousand, three hundred fifty-one".