74207752921 has 3 divisors (see below), whose sum is σ = 74208025333. Its totient is φ = 74207480510.

The previous prime is 74207752909. The next prime is 74207752939. The reversal of 74207752921 is 12925770247.

The square root of 74207752921 is 272411.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12925770247 = 13 ⋅994290019.

It is not a de Polignac number, because 74207752921 - 2¹³ = 74207744729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (74207752981) 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, 136206 + ... + 408616.

Almost surely, 2^74207752921 is an apocalyptic number.

74207752921 is the 272411-st square number.

74207752921 is the 136206-th centered octagonal number.

It is an amenable number.

74207752921 is a deficient number, since it is larger than the sum of its proper divisors (272412).

74207752921 is an frugal number, since it uses more digits than its factorization.

74207752921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544822 (or 272411 counting only the distinct ones).

The product of its (nonzero) digits is 493920, while the sum is 46.

The spelling of 74207752921 in words is "seventy-four billion, two hundred seven million, seven hundred fifty-two thousand, nine hundred twenty-one".