21377730258 has 12 divisors (see below), whose sum is σ = 46318415598. Its totient is φ = 7125910080.

The previous prime is 21377730251. The next prime is 21377730301. The reversal of 21377730258 is 85203777312.

It is a happy number.

21377730258 is a `hidden beast` number, since 21 + 377 + 7 + 3 + 0 + 258 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19831117329 + 1546612929 = 140823^2 + 39327^2 .

It is not an unprimeable number, because it can be changed into a prime (21377730251) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 593825823 + ... + 593825858.

Almost surely, 2^21377730258 is an apocalyptic number.

21377730258 is an abundant number, since it is smaller than the sum of its proper divisors (24940685340).

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

21377730258 is a wasteful number, since it uses less digits than its factorization.

21377730258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1187651689 (or 1187651686 counting only the distinct ones).

The product of its (nonzero) digits is 493920, while the sum is 45.

The spelling of 21377730258 in words is "twenty-one billion, three hundred seventy-seven million, seven hundred thirty thousand, two hundred fifty-eight".