21251819055430 has 16 divisors (see below), whose sum is σ = 38260972774080. Its totient is φ = 8499016850112.

The previous prime is 21251819055427. The next prime is 21251819055449. The reversal of 21251819055430 is 3455091815212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 213794334 + ... + 213893713.

It is an arithmetic number, because the mean of its divisors is an integer number (2391310798380).

Almost surely, 2^{21251819055430} is an apocalyptic number.

21251819055430 is a deficient number, since it is larger than the sum of its proper divisors (17009153718650).

21251819055430 is a wasteful number, since it uses less digits than its factorization.

21251819055430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427693023.

The product of its (nonzero) digits is 432000, while the sum is 46.

The spelling of 21251819055430 in words is "twenty-one trillion, two hundred fifty-one billion, eight hundred nineteen million, fifty-five thousand, four hundred thirty".