21570401223 has 32 divisors (see below), whose sum is σ = 36528299520. Its totient is φ = 12323586240.

The previous prime is 21570401219. The next prime is 21570401249. The reversal of 21570401223 is 32210407512.

21570401223 is a `hidden beast` number, since 21 + 570 + 40 + 12 + 23 = 666.

It is not a de Polignac number, because 21570401223 - 2² = 21570401219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21570401123) 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, 1634136 + ... + 1647282.

It is an arithmetic number, because the mean of its divisors is an integer number (1141509360).

Almost surely, 2^21570401223 is an apocalyptic number.

21570401223 is a deficient number, since it is larger than the sum of its proper divisors (14957898297).

21570401223 is a wasteful number, since it uses less digits than its factorization.

21570401223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21844 (or 21838 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

Adding to 21570401223 its reverse (32210407512), we get a palindrome (53780808735).

The spelling of 21570401223 in words is "twenty-one billion, five hundred seventy million, four hundred one thousand, two hundred twenty-three".