840972149 has 4 divisors (see below), whose sum is σ = 863701164. Its totient is φ = 818243136.

The previous prime is 840972137. The next prime is 840972163. The reversal of 840972149 is 941279048.

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

It can be written as a sum of positive squares in 2 ways, for example, as 738861124 + 102111025 = 27182^2 + 10105^2 .

It is a cyclic number.

It is not a de Polignac number, because 840972149 - 2¹⁶ = 840906613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840972109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11364452 + ... + 11364525.

It is an arithmetic number, because the mean of its divisors is an integer number (215925291).

Almost surely, 2^840972149 is an apocalyptic number.

It is an amenable number.

840972149 is a deficient number, since it is larger than the sum of its proper divisors (22729015).

840972149 is a wasteful number, since it uses less digits than its factorization.

840972149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22729014.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 840972149 is about 28999.5198063692. The cubic root of 840972149 is about 943.9026479164.

The spelling of 840972149 in words is "eight hundred forty million, nine hundred seventy-two thousand, one hundred forty-nine".