21406213058 has 4 divisors (see below), whose sum is σ = 32109319590. Its totient is φ = 10703106528.

The previous prime is 21406213057. The next prime is 21406213069. The reversal of 21406213058 is 85031260412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20763945409 + 642267649 = 144097^2 + 25343^2 .

It is a super-3 number, since 3×21406213058³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21406213057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5351553263 + ... + 5351553266.

Almost surely, 2^21406213058 is an apocalyptic number.

21406213058 is a deficient number, since it is larger than the sum of its proper divisors (10703106532).

21406213058 is a wasteful number, since it uses less digits than its factorization.

21406213058 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10703106531.

The product of its (nonzero) digits is 11520, while the sum is 32.

The spelling of 21406213058 in words is "twenty-one billion, four hundred six million, two hundred thirteen thousand, fifty-eight".