40396578121 has 3 divisors (see below), whose sum is σ = 40396779111. Its totient is φ = 40396377132.

The previous prime is 40396578097. The next prime is 40396578179. The reversal of 40396578121 is 12187569304.

The square root of 40396578121 is 200989.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 36000888121 + 4395690000 = 189739^2 + 66300^2 .

It is not a de Polignac number, because 40396578121 - 2⁷ = 40396577993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40396570121) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 100495 + ... + 301483.

It is an arithmetic number, because the mean of its divisors is an integer number (13465593037).

It is a 2-persistent number, because it is pandigital, and so is 2⋅40396578121 = 80793156242, but 3⋅40396578121 = 121189734363 is not.

Almost surely, 2^40396578121 is an apocalyptic number.

40396578121 is the 200989-th square number.

40396578121 is the 100495-th centered octagonal number.

It is an amenable number.

40396578121 is a deficient number, since it is larger than the sum of its proper divisors (200990).

40396578121 is an frugal number, since it uses more digits than its factorization.

40396578121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401978 (or 200989 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 40396578121 in words is "forty billion, three hundred ninety-six million, five hundred seventy-eight thousand, one hundred twenty-one".