137778861 has 32 divisors (see below), whose sum is σ = 216691200. Its totient is φ = 76956480.

The previous prime is 137778811. The next prime is 137778869. The reversal of 137778861 is 168877731.

137778861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 137778861 - 2¹¹ = 137776813 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 137778861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (137778869) 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, 20230 + ... + 26168.

It is an arithmetic number, because the mean of its divisors is an integer number (6771600).

Almost surely, 2^137778861 is an apocalyptic number.

137778861 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

137778861 is a deficient number, since it is larger than the sum of its proper divisors (78912339).

137778861 is a wasteful number, since it uses less digits than its factorization.

137778861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6009.

The product of its digits is 395136, while the sum is 48.

The square root of 137778861 is about 11737.9240498480. The cubic root of 137778861 is about 516.4887465541.

The spelling of 137778861 in words is "one hundred thirty-seven million, seven hundred seventy-eight thousand, eight hundred sixty-one".