21697536044 has 6 divisors (see below), whose sum is σ = 37970688084. Its totient is φ = 10848768020.

The previous prime is 21697536017. The next prime is 21697536053. The reversal of 21697536044 is 44063579612.

It is a self number, because there is not a number n which added to its sum of digits gives 21697536044.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2712192002 + ... + 2712192009.

It is an arithmetic number, because the mean of its divisors is an integer number (6328448014).

Almost surely, 2^21697536044 is an apocalyptic number.

It is an amenable number.

21697536044 is a deficient number, since it is larger than the sum of its proper divisors (16273152040).

21697536044 is a wasteful number, since it uses less digits than its factorization.

21697536044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5424384015 (or 5424384013 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 47.

The spelling of 21697536044 in words is "twenty-one billion, six hundred ninety-seven million, five hundred thirty-six thousand, forty-four".