420507428 has 18 divisors (see below), whose sum is σ = 808869558. Its totient is φ = 191139520.

The previous prime is 420507421. The next prime is 420507431. The reversal of 420507428 is 824705024.

It can be written as a sum of positive squares in only one way, i.e., 417711844 + 2795584 = 20438^2 + 1672^2 .

It is a junction number, because it is equal to n+sod(n) for n = 420507394 and 420507403.

It is not an unprimeable number, because it can be changed into a prime (420507421) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 433925 + ... + 434892.

Almost surely, 2^420507428 is an apocalyptic number.

It is an amenable number.

420507428 is a deficient number, since it is larger than the sum of its proper divisors (388362130).

420507428 is a wasteful number, since it uses less digits than its factorization.

420507428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 868843 (or 868830 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 32.

The square root of 420507428 is about 20506.2777704780. The cubic root of 420507428 is about 749.1887096901.

The spelling of 420507428 in words is "four hundred twenty million, five hundred seven thousand, four hundred twenty-eight".