21267815970 has 32 divisors (see below), whose sum is σ = 51046822080. Its totient is φ = 5670966080.

The previous prime is 21267815957. The next prime is 21267816127. The reversal of 21267815970 is 7951876212.

It is a super-2 number, since 2×21267815970² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 547285 + ... + 584855.

It is an arithmetic number, because the mean of its divisors is an integer number (1595213190).

Almost surely, 2^21267815970 is an apocalyptic number.

21267815970 is an abundant number, since it is smaller than the sum of its proper divisors (29779006110).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21267815970 is a wasteful number, since it uses less digits than its factorization.

21267815970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56450.

The product of its (nonzero) digits is 423360, while the sum is 48.

The spelling of 21267815970 in words is "twenty-one billion, two hundred sixty-seven million, eight hundred fifteen thousand, nine hundred seventy".