61818420 has 24 divisors (see below), whose sum is σ = 173091744. Its totient is φ = 16484896.

The previous prime is 61818389. The next prime is 61818431. The reversal of 61818420 is 2481816.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 515094 + ... + 515213.

It is an arithmetic number, because the mean of its divisors is an integer number (7212156).

Almost surely, 2^61818420 is an apocalyptic number.

61818420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61818420 is an abundant number, since it is smaller than the sum of its proper divisors (111273324).

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

61818420 is a wasteful number, since it uses less digits than its factorization.

61818420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1030319 (or 1030317 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 61818420 is about 7862.4690778406. The cubic root of 61818420 is about 395.4023993024.

The spelling of 61818420 in words is "sixty-one million, eight hundred eighteen thousand, four hundred twenty".