420645642545 has 4 divisors (see below), whose sum is σ = 504774771060. Its totient is φ = 336516514032.

The previous prime is 420645642539. The next prime is 420645642569. The reversal of 420645642545 is 545246546024.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 127203502336 + 293442140209 = 356656^2 + 541703^2 .

It is a cyclic number.

It is not a de Polignac number, because 420645642545 - 2⁶ = 420645642481 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 420645642545.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42064564250 + ... + 42064564259.

It is an arithmetic number, because the mean of its divisors is an integer number (126193692765).

Almost surely, 2^420645642545 is an apocalyptic number.

It is an amenable number.

420645642545 is a deficient number, since it is larger than the sum of its proper divisors (84129128515).

420645642545 is an equidigital number, since it uses as much as digits as its factorization.

420645642545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84129128514.

The product of its (nonzero) digits is 4608000, while the sum is 47.

The spelling of 420645642545 in words is "four hundred twenty billion, six hundred forty-five million, six hundred forty-two thousand, five hundred forty-five".