61788155 has 32 divisors (see below), whose sum is σ = 88058880. Its totient is φ = 41028480.

The previous prime is 61788131. The next prime is 61788169. The reversal of 61788155 is 55188716.

It is not a de Polignac number, because 61788155 - 2⁶ = 61788091 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73226 + ... + 74064.

It is an arithmetic number, because the mean of its divisors is an integer number (2751840).

Almost surely, 2^61788155 is an apocalyptic number.

61788155 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

61788155 is a deficient number, since it is larger than the sum of its proper divisors (26270725).

61788155 is a wasteful number, since it uses less digits than its factorization.

61788155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 971.

The product of its digits is 67200, while the sum is 41.

The square root of 61788155 is about 7860.5441923572. The cubic root of 61788155 is about 395.3378618660.

The spelling of 61788155 in words is "sixty-one million, seven hundred eighty-eight thousand, one hundred fifty-five".