21132907 has 2 divisors, whose sum is σ = 21132908. Its totient is φ = 21132906.

The previous prime is 21132899. The next prime is 21132931. The reversal of 21132907 is 70923112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21132907 - 2³ = 21132899 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566453 + 10566454.

It is an arithmetic number, because the mean of its divisors is an integer number (10566454).

Almost surely, 2^21132907 is an apocalyptic number.

21132907 is a deficient number, since it is larger than the sum of its proper divisors (1).

21132907 is an equidigital number, since it uses as much as digits as its factorization.

21132907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 21132907 is about 4597.0541654412. The cubic root of 21132907 is about 276.4732263402.

The spelling of 21132907 in words is "twenty-one million, one hundred thirty-two thousand, nine hundred seven".