61778400 has 72 divisors (see below), whose sum is σ = 201096504. Its totient is φ = 16473600.

The previous prime is 61778383. The next prime is 61778407. The reversal of 61778400 is 487716.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61778407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10471 + ... + 15270.

It is an arithmetic number, because the mean of its divisors is an integer number (2793007).

Almost surely, 2^61778400 is an apocalyptic number.

61778400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61778400 is an abundant number, since it is smaller than the sum of its proper divisors (139318104).

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

61778400 is a wasteful number, since it uses less digits than its factorization.

61778400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25764 (or 25751 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 61778400 is about 7859.9236637514. The cubic root of 61778400 is about 395.3170557001.

The spelling of 61778400 in words is "sixty-one million, seven hundred seventy-eight thousand, four hundred".