1251423055021 has 8 divisors (see below), whose sum is σ = 1256594062464. Its totient is φ = 1246256115840.

The previous prime is 1251423054997. The next prime is 1251423055027. The reversal of 1251423055021 is 1205503241521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1251423055021 - 2¹³ = 1251423046829 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 (1251423055027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 399811 + ... + 1631776.

It is an arithmetic number, because the mean of its divisors is an integer number (157074257808).

Almost surely, 2^{1251423055021} is an apocalyptic number.

It is an amenable number.

1251423055021 is a deficient number, since it is larger than the sum of its proper divisors (5171007443).

1251423055021 is a wasteful number, since it uses less digits than its factorization.

1251423055021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2034131.

The product of its (nonzero) digits is 12000, while the sum is 31.

Adding to 1251423055021 its reverse (1205503241521), we get a palindrome (2456926296542).

The spelling of 1251423055021 in words is "one trillion, two hundred fifty-one billion, four hundred twenty-three million, fifty-five thousand, twenty-one".