420507891 has 24 divisors (see below), whose sum is σ = 612806480. Its totient is φ = 277857216.

The previous prime is 420507877. The next prime is 420507907. The reversal of 420507891 is 198705024.

It is not a de Polignac number, because 420507891 - 2⁹ = 420507379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420507991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 768480 + ... + 769026.

Almost surely, 2^420507891 is an apocalyptic number.

420507891 is a deficient number, since it is larger than the sum of its proper divisors (192298589).

420507891 is a wasteful number, since it uses less digits than its factorization.

420507891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1155 (or 1152 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 420507891 is about 20506.2890597007. The cubic root of 420507891 is about 749.1889846549.

The spelling of 420507891 in words is "four hundred twenty million, five hundred seven thousand, eight hundred ninety-one".