2138084403961 has 9 divisors (see below), whose sum is σ = 2350143512143. Its totient is φ = 1943698472320.

The previous prime is 2138084403937. The next prime is 2138084403967. The reversal of 2138084403961 is 1693044808312.

It is a happy number.

The square root of 2138084403961 is 1462219.

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

It can be written as a sum of positive squares in only one way, i.e., 1596859341561 + 541225062400 = 1263669^2 + 735680^2 .

It is not a de Polignac number, because 2138084403961 - 2⁹ = 2138084403449 is a prime.

It is a super-2 number, since 2×2138084403961² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2138084403967) 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, 16017945 + ... + 16150873.

Almost surely, 2^{2138084403961} is an apocalyptic number.

2138084403961 is the 1462219-th square number.

2138084403961 is the 731110-th centered octagonal number.

It is an amenable number.

2138084403961 is a deficient number, since it is larger than the sum of its proper divisors (212059108182).

2138084403961 is an frugal number, since it uses more digits than its factorization.

2138084403961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265880 (or 132940 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 49.

Multiplying 2138084403961 by its sum of digits (49), we get a square (104766135794089 = 10235533²).

The spelling of 2138084403961 in words is "two trillion, one hundred thirty-eight billion, eighty-four million, four hundred three thousand, nine hundred sixty-one".