61491474 has 60 divisors (see below), whose sum is σ = 151499502. Its totient is φ = 18627840.

The previous prime is 61491457. The next prime is 61491481. The reversal of 61491474 is 47419416.

It can be written as a sum of positive squares in only one way, i.e., 31843449 + 29648025 = 5643^2 + 5445^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 18034 + ... + 21170.

Almost surely, 2^61491474 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61491474, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75749751).

61491474 is an abundant number, since it is smaller than the sum of its proper divisors (90008028).

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

61491474 is a wasteful number, since it uses less digits than its factorization.

61491474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3173 (or 3153 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 61491474 is about 7841.6499539319. The cubic root of 61491474 is about 394.7040971406.

The spelling of 61491474 in words is "sixty-one million, four hundred ninety-one thousand, four hundred seventy-four".