61690429440 has 420 divisors, whose sum is σ = 222192109524. Its totient is φ = 16434855936.

The previous prime is 61690429439. The next prime is 61690429453. The reversal of 61690429440 is 4492409616.

61690429440 is a `hidden beast` number, since 6 + 169 + 0 + 42 + 9 + 440 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 44443385856 + 17247043584 = 210816^2 + 131328^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 59719164 + ... + 59720196.

Almost surely, 2^61690429440 is an apocalyptic number.

61690429440 is a gapful number since it is divisible by the number (60) 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 61690429440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111096054762).

61690429440 is an abundant number, since it is smaller than the sum of its proper divisors (160501680084).

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

61690429440 is an frugal number, since it uses more digits than its factorization.

61690429440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1084 (or 1043 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 61690429440 in words is "sixty-one billion, six hundred ninety million, four hundred twenty-nine thousand, four hundred forty".