20821120434 has 24 divisors (see below), whose sum is σ = 45272981052. Its totient is φ = 6915672960.

The previous prime is 20821120433. The next prime is 20821120451. The reversal of 20821120434 is 43402112802.

20821120434 is a `hidden beast` number, since 208 + 2 + 1 + 1 + 20 + 434 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 17057666025 + 3763454409 = 130605^2 + 61347^2 .

It is a super-2 number, since 2×20821120434² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20821120398 and 20821120407.

It is not an unprimeable number, because it can be changed into a prime (20821120433) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2053179 + ... + 2063294.

Almost surely, 2^20821120434 is an apocalyptic number.

20821120434 is an abundant number, since it is smaller than the sum of its proper divisors (24451860618).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20821120434 is a wasteful number, since it uses less digits than its factorization.

20821120434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4116762 (or 4116759 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The spelling of 20821120434 in words is "twenty billion, eight hundred twenty-one million, one hundred twenty thousand, four hundred thirty-four".