21167049121 has 9 divisors (see below), whose sum is σ = 21471754329. Its totient is φ = 20866614336.

The previous prime is 21167049103. The next prime is 21167049139. The reversal of 21167049121 is 12194076112.

The square root of 21167049121 is 145489.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (21167049103) and next prime (21167049139).

It can be written as a sum of positive squares in 4 ways, for example, as 1957089121 + 19209960000 = 44239^2 + 138600^2 .

It is not a de Polignac number, because 21167049121 - 2⁵ = 21167049089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21167049191) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 10619701 + ... + 10621693.

It is an arithmetic number, because the mean of its divisors is an integer number (2385750481).

Almost surely, 2^21167049121 is an apocalyptic number.

21167049121 is the 145489-th square number.

21167049121 is the 72745-th centered octagonal number.

It is an amenable number.

21167049121 is a deficient number, since it is larger than the sum of its proper divisors (304705208).

21167049121 is an frugal number, since it uses more digits than its factorization.

21167049121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4132 (or 2066 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 34.

The spelling of 21167049121 in words is "twenty-one billion, one hundred sixty-seven million, forty-nine thousand, one hundred twenty-one".