21772507 has 2 divisors, whose sum is σ = 21772508. Its totient is φ = 21772506.

The previous prime is 21772481. The next prime is 21772519. The reversal of 21772507 is 70527712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21772507 - 2⁷ = 21772379 is a prime.

It is a super-2 number, since 2×21772507² = 948084122130098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21772567) 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, 10886253 + 10886254.

It is an arithmetic number, because the mean of its divisors is an integer number (10886254).

Almost surely, 2^21772507 is an apocalyptic number.

21772507 is a deficient number, since it is larger than the sum of its proper divisors (1).

21772507 is an equidigital number, since it uses as much as digits as its factorization.

21772507 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6860, while the sum is 31.

The square root of 21772507 is about 4666.1019063025. The cubic root of 21772507 is about 279.2347599941.

The spelling of 21772507 in words is "twenty-one million, seven hundred seventy-two thousand, five hundred seven".