238711393561 has 9 divisors (see below), whose sum is σ = 239633958229. Its totient is φ = 237792372700.

The previous prime is 238711393519. The next prime is 238711393597. The reversal of 238711393561 is 165393117832.

The square root of 238711393561 is 488581.

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

It is not a de Polignac number, because 238711393561 - 2¹³ = 238711385369 is a prime.

It is a super-3 number, since 3×238711393561³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (238711394561) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 151947906 + ... + 151949476.

Almost surely, 2^238711393561 is an apocalyptic number.

238711393561 is the 488581-st square number.

238711393561 is the 244291-st centered octagonal number.

It is an amenable number.

238711393561 is a deficient number, since it is larger than the sum of its proper divisors (922564668).

238711393561 is an frugal number, since it uses more digits than its factorization.

238711393561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3764 (or 1882 counting only the distinct ones).

The product of its digits is 816480, while the sum is 49.

Multiplying 238711393561 by its sum of digits (49), we get a square (11696858284489 = 3420067²).

The spelling of 238711393561 in words is "two hundred thirty-eight billion, seven hundred eleven million, three hundred ninety-three thousand, five hundred sixty-one".