21047607 has 30 divisors (see below), whose sum is σ = 36581688. Its totient is φ = 12024936.

The previous prime is 21047603. The next prime is 21047617. The reversal of 21047607 is 70674012.

21047607 is a `hidden beast` number, since 2 + 10 + 47 + 607 = 666.

It is not a de Polignac number, because 21047607 - 2² = 21047603 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21047603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1318 + ... + 6620.

Almost surely, 2^21047607 is an apocalyptic number.

21047607 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21047607 is a deficient number, since it is larger than the sum of its proper divisors (15534081).

21047607 is an equidigital number, since it uses as much as digits as its factorization.

21047607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5329 (or 5313 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 21047607 is about 4587.7671039407. The cubic root of 21047607 is about 276.1007429964.

The spelling of 21047607 in words is "twenty-one million, forty-seven thousand, six hundred seven".