21301497 has 12 divisors (see below), whose sum is σ = 35164480. Its totient is φ = 12172248.

The previous prime is 21301471. The next prime is 21301507. The reversal of 21301497 is 79410312.

It is not a de Polignac number, because 21301497 - 2¹⁴ = 21285113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21301497.

It is not an unprimeable number, because it can be changed into a prime (21301097) 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 11 ways as a sum of consecutive naturals, for example, 168997 + ... + 169122.

Almost surely, 2^21301497 is an apocalyptic number.

It is an amenable number.

21301497 is a deficient number, since it is larger than the sum of its proper divisors (13862983).

21301497 is a wasteful number, since it uses less digits than its factorization.

21301497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338132 (or 338129 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21301497 is about 4615.3544825939. The cubic root of 21301497 is about 277.2064780505.

The spelling of 21301497 in words is "twenty-one million, three hundred one thousand, four hundred ninety-seven".