20421853031 has 2 divisors, whose sum is σ = 20421853032. Its totient is φ = 20421853030.

The previous prime is 20421852931. The next prime is 20421853033. The reversal of 20421853031 is 13035812402.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20421853031 - 2²² = 20417658727 is a prime.

It is a super-2 number, since 2×20421853031² (a number of 21 digits) contains 22 as substring.

Together with 20421853033, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20421852985 and 20421853003.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20421853033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10210926515 + 10210926516.

It is an arithmetic number, because the mean of its divisors is an integer number (10210926516).

Almost surely, 2^20421853031 is an apocalyptic number.

20421853031 is a deficient number, since it is larger than the sum of its proper divisors (1).

20421853031 is an equidigital number, since it uses as much as digits as its factorization.

20421853031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 29.

The spelling of 20421853031 in words is "twenty billion, four hundred twenty-one million, eight hundred fifty-three thousand, thirty-one".