61405400 has 96 divisors (see below), whose sum is σ = 170346240. Its totient is φ = 20127360.

The previous prime is 61405391. The next prime is 61405403. The reversal of 61405400 is 450416.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61405403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31247 + ... + 33153.

It is an arithmetic number, because the mean of its divisors is an integer number (1774440).

Almost surely, 2^61405400 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 61405400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85173120).

61405400 is an abundant number, since it is smaller than the sum of its proper divisors (108940840).

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

61405400 is a wasteful number, since it uses less digits than its factorization.

61405400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1953 (or 1944 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 61405400 is about 7836.1597737667. The cubic root of 61405400 is about 394.5198459894.

Adding to 61405400 its reverse (450416), we get a palindrome (61855816).

The spelling of 61405400 in words is "sixty-one million, four hundred five thousand, four hundred".