420705731021 has 4 divisors (see below), whose sum is σ = 420758571552. Its totient is φ = 420652890492.

The previous prime is 420705731011. The next prime is 420705731023. The reversal of 420705731021 is 120137507024.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420705731021 is a prime.

It is a super-2 number, since 2×420705731021² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420705731023) 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, 26408321 + ... + 26424246.

It is an arithmetic number, because the mean of its divisors is an integer number (105189642888).

Almost surely, 2^420705731021 is an apocalyptic number.

It is an amenable number.

420705731021 is a deficient number, since it is larger than the sum of its proper divisors (52840531).

420705731021 is an equidigital number, since it uses as much as digits as its factorization.

420705731021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52840530.

The product of its (nonzero) digits is 11760, while the sum is 32.

The spelling of 420705731021 in words is "four hundred twenty billion, seven hundred five million, seven hundred thirty-one thousand, twenty-one".