20434313021 has 16 divisors (see below), whose sum is σ = 22810737600. Its totient is φ = 18191547648.

The previous prime is 20434312979. The next prime is 20434313023. The reversal of 20434313021 is 12031343402.

It is a cyclic number.

It is not a de Polignac number, because 20434313021 - 2¹⁴ = 20434296637 is a prime.

It is a super-2 number, since 2×20434313021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20434313023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158495 + ... + 256883.

It is an arithmetic number, because the mean of its divisors is an integer number (1425671100).

Almost surely, 2^20434313021 is an apocalyptic number.

It is an amenable number.

20434313021 is a deficient number, since it is larger than the sum of its proper divisors (2376424579).

20434313021 is a wasteful number, since it uses less digits than its factorization.

20434313021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99068.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 20434313021 its reverse (12031343402), we get a palindrome (32465656423).

The spelling of 20434313021 in words is "twenty billion, four hundred thirty-four million, three hundred thirteen thousand, twenty-one".