21492061 has 2 divisors, whose sum is σ = 21492062. Its totient is φ = 21492060.

The previous prime is 21492043. The next prime is 21492067. The reversal of 21492061 is 16029412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21483225 + 8836 = 4635^2 + 94^2 .

It is a cyclic number.

It is not a de Polignac number, because 21492061 - 2¹¹ = 21490013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21492067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10746030 + 10746031.

It is an arithmetic number, because the mean of its divisors is an integer number (10746031).

Almost surely, 2^21492061 is an apocalyptic number.

It is an amenable number.

21492061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21492061 is an equidigital number, since it uses as much as digits as its factorization.

21492061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 21492061 is about 4635.9530843183. The cubic root of 21492061 is about 278.0306584203.

The spelling of 21492061 in words is "twenty-one million, four hundred ninety-two thousand, sixty-one".