20711421 has 6 divisors (see below), whose sum is σ = 29916510. Its totient is φ = 13807608.

The previous prime is 20711413. The next prime is 20711459. The reversal of 20711421 is 12411702.

It can be written as a sum of positive squares in only one way, i.e., 20602521 + 108900 = 4539^2 + 330^2 .

It is not a de Polignac number, because 20711421 - 2³ = 20711413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20711394 and 20711403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20711401) 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, 1150626 + ... + 1150643.

It is an arithmetic number, because the mean of its divisors is an integer number (4986085).

Almost surely, 2^20711421 is an apocalyptic number.

It is an amenable number.

20711421 is a deficient number, since it is larger than the sum of its proper divisors (9205089).

20711421 is a wasteful number, since it uses less digits than its factorization.

20711421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2301275 (or 2301272 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 20711421 is about 4550.9802240836. The cubic root of 20711421 is about 274.6228261778.

It can be divided in two parts, 207 and 11421, that added together give a triangular number (11628 = T₁₅₂).

The spelling of 20711421 in words is "twenty million, seven hundred eleven thousand, four hundred twenty-one".