61557408 has 240 divisors, whose sum is σ = 210760704. Its totient is φ = 17418240.

The previous prime is 61557403. The next prime is 61557427. The reversal of 61557408 is 80475516.

61557408 is a `hidden beast` number, since 61 + 557 + 40 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (61557403) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 484641 + ... + 484767.

Almost surely, 2^61557408 is an apocalyptic number.

61557408 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61557408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105380352).

61557408 is an abundant number, since it is smaller than the sum of its proper divisors (149203296).

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

61557408 is a wasteful number, since it uses less digits than its factorization.

61557408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 61557408 is about 7845.8529173061. The cubic root of 61557408 is about 394.8451200730.

The spelling of 61557408 in words is "sixty-one million, five hundred fifty-seven thousand, four hundred eight".