21125151061 has 4 divisors (see below), whose sum is σ = 24143029792. Its totient is φ = 18107272332.

The previous prime is 21125151059. The next prime is 21125151101. The reversal of 21125151061 is 16015152112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21125151061 - 2¹ = 21125151059 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21125151041) 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 3 ways as a sum of consecutive naturals, for example, 1508939355 + ... + 1508939368.

It is an arithmetic number, because the mean of its divisors is an integer number (6035757448).

Almost surely, 2^21125151061 is an apocalyptic number.

It is an amenable number.

21125151061 is a deficient number, since it is larger than the sum of its proper divisors (3017878731).

21125151061 is an equidigital number, since it uses as much as digits as its factorization.

21125151061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3017878730.

The product of its (nonzero) digits is 600, while the sum is 25.

The spelling of 21125151061 in words is "twenty-one billion, one hundred twenty-five million, one hundred fifty-one thousand, sixty-one".