21047297901 has 32 divisors (see below), whose sum is σ = 32437048320. Its totient is φ = 11890934784.

The previous prime is 21047297881. The next prime is 21047297911. The reversal of 21047297901 is 10979274012.

It is not a de Polignac number, because 21047297901 - 2⁷ = 21047297773 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21047297911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 644710 + ... + 676568.

It is an arithmetic number, because the mean of its divisors is an integer number (1013657760).

Almost surely, 2^21047297901 is an apocalyptic number.

21047297901 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21047297901 is a deficient number, since it is larger than the sum of its proper divisors (11389750419).

21047297901 is a wasteful number, since it uses less digits than its factorization.

21047297901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32225.

The product of its (nonzero) digits is 63504, while the sum is 42.

The spelling of 21047297901 in words is "twenty-one billion, forty-seven million, two hundred ninety-seven thousand, nine hundred one".