21154541234 has 16 divisors (see below), whose sum is σ = 32530215168. Its totient is φ = 10312848192.

The previous prime is 21154541227. The next prime is 21154541269. The reversal of 21154541234 is 43214545112.

It is a super-2 number, since 2×21154541234² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21154541234.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 403127 + ... + 452570.

It is an arithmetic number, because the mean of its divisors is an integer number (2033138448).

Almost surely, 2^21154541234 is an apocalyptic number.

21154541234 is a deficient number, since it is larger than the sum of its proper divisors (11375673934).

21154541234 is a wasteful number, since it uses less digits than its factorization.

21154541234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 856009.

The product of its digits is 19200, while the sum is 32.

The spelling of 21154541234 in words is "twenty-one billion, one hundred fifty-four million, five hundred forty-one thousand, two hundred thirty-four".