21298047897 has 16 divisors (see below), whose sum is σ = 32864983040. Its totient is φ = 12016257552.

The previous prime is 21298047889. The next prime is 21298047919. The reversal of 21298047897 is 79874089212.

It is not a de Polignac number, because 21298047897 - 2³ = 21298047889 is a prime.

It is a super-2 number, since 2×21298047897² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21298047857) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6417283 + ... + 6420600.

It is an arithmetic number, because the mean of its divisors is an integer number (2054061440).

Almost surely, 2^21298047897 is an apocalyptic number.

It is an amenable number.

21298047897 is a deficient number, since it is larger than the sum of its proper divisors (11566935143).

21298047897 is a wasteful number, since it uses less digits than its factorization.

21298047897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12837972.

The product of its (nonzero) digits is 4064256, while the sum is 57.

The spelling of 21298047897 in words is "twenty-one billion, two hundred ninety-eight million, forty-seven thousand, eight hundred ninety-seven".