21046429 has 2 divisors, whose sum is σ = 21046430. Its totient is φ = 21046428.

The previous prime is 21046409. The next prime is 21046447. The reversal of 21046429 is 92464012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13675204 + 7371225 = 3698^2 + 2715^2 .

It is a cyclic number.

It is not a de Polignac number, because 21046429 - 2⁷ = 21046301 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21046397 and 21046406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21046409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10523214 + 10523215.

It is an arithmetic number, because the mean of its divisors is an integer number (10523215).

Almost surely, 2^21046429 is an apocalyptic number.

It is an amenable number.

21046429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21046429 is an equidigital number, since it uses as much as digits as its factorization.

21046429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 21046429 is about 4587.6387172488. The cubic root of 21046429 is about 276.0955919319.

The spelling of 21046429 in words is "twenty-one million, forty-six thousand, four hundred twenty-nine".