207972138 has 48 divisors (see below), whose sum is σ = 481289760. Its totient is φ = 59700960.

The previous prime is 207972113. The next prime is 207972139. The reversal of 207972138 is 831279702.

207972138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 207972096 and 207972105.

It is not an unprimeable number, because it can be changed into a prime (207972139) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6256 + ... + 21332.

It is an arithmetic number, because the mean of its divisors is an integer number (10026870).

Almost surely, 2^207972138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 207972138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (240644880).

207972138 is an abundant number, since it is smaller than the sum of its proper divisors (273317622).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

207972138 is a wasteful number, since it uses less digits than its factorization.

207972138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15123 (or 15112 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 39.

The square root of 207972138 is about 14421.2391284522. The cubic root of 207972138 is about 592.4727570304.

The spelling of 207972138 in words is "two hundred seven million, nine hundred seventy-two thousand, one hundred thirty-eight".