61991748 has 144 divisors (see below), whose sum is σ = 195686400. Its totient is φ = 16111872.

The previous prime is 61991719. The next prime is 61991753. The reversal of 61991748 is 84719916.

It is a happy number.

61991748 is digitally balanced in base 9, 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 (45) coincides with the sum of the digits of its prime factors.

61991748 is strictly pandigital in base 9.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 415978 + ... + 416126.

Almost surely, 2^61991748 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61991748, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97843200).

61991748 is an abundant number, since it is smaller than the sum of its proper divisors (133694652).

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

61991748 is a wasteful number, since it uses less digits than its factorization.

61991748 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 301 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 61991748 is about 7873.4838540509. The cubic root of 61991748 is about 395.7716007688.

The spelling of 61991748 in words is "sixty-one million, nine hundred ninety-one thousand, seven hundred forty-eight".