740840015521 has 4 divisors (see below), whose sum is σ = 740844429444. Its totient is φ = 740835601600.

The previous prime is 740840015519. The next prime is 740840015537. The reversal of 740840015521 is 125510048047.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 125510048047 = 6673 ⋅18808639.

It can be written as a sum of positive squares in 2 ways, for example, as 74389835025 + 666450180496 = 272745^2 + 816364^2 .

It is a cyclic number.

It is not a de Polignac number, because 740840015521 - 2¹ = 740840015519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (740840015621) 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, 1944820 + ... + 2294341.

It is an arithmetic number, because the mean of its divisors is an integer number (185211107361).

Almost surely, 2^740840015521 is an apocalyptic number.

It is an amenable number.

740840015521 is a deficient number, since it is larger than the sum of its proper divisors (4413923).

740840015521 is a wasteful number, since it uses less digits than its factorization.

740840015521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4413922.

The product of its (nonzero) digits is 44800, while the sum is 37.

The spelling of 740840015521 in words is "seven hundred forty billion, eight hundred forty million, fifteen thousand, five hundred twenty-one".