49657219921 has 3 divisors (see below), whose sum is σ = 49657442761. Its totient is φ = 49656997082.

The previous prime is 49657219907. The next prime is 49657219933. The reversal of 49657219921 is 12991275694.

It is a happy number.

The square root of 49657219921 is 222839.

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 is not a de Polignac number, because 49657219921 - 2¹¹ = 49657217873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (49657210921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 111420 + ... + 334258.

Almost surely, 2^49657219921 is an apocalyptic number.

49657219921 is the 222839-th square number.

49657219921 is the 111420-th centered octagonal number.

It is an amenable number.

49657219921 is a deficient number, since it is larger than the sum of its proper divisors (222840).

49657219921 is an frugal number, since it uses more digits than its factorization.

49657219921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445678 (or 222839 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 55.

The spelling of 49657219921 in words is "forty-nine billion, six hundred fifty-seven million, two hundred nineteen thousand, nine hundred twenty-one".