238640156397 has 32 divisors (see below), whose sum is σ = 365081974400. Its totient is φ = 153967879296.

The previous prime is 238640156387. The next prime is 238640156399. The reversal of 238640156397 is 793651046832.

238640156397 is a `hidden beast` number, since 2 + 38 + 6 + 40 + 1 + 563 + 9 + 7 = 666.

It is not a de Polignac number, because 238640156397 - 2²³ = 238631767789 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 (238640156399) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 816328 + ... + 1069425.

It is an arithmetic number, because the mean of its divisors is an integer number (11408811700).

It is a 1-persistent number, because it is pandigital, but 2⋅238640156397 = 477280312794 is not.

Almost surely, 2^238640156397 is an apocalyptic number.

238640156397 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

238640156397 is a deficient number, since it is larger than the sum of its proper divisors (126441818003).

238640156397 is a wasteful number, since it uses less digits than its factorization.

238640156397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1885914 (or 1885908 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 54.

The spelling of 238640156397 in words is "two hundred thirty-eight billion, six hundred forty million, one hundred fifty-six thousand, three hundred ninety-seven".