74551420661 has 4 divisors (see below), whose sum is σ = 74557091532. Its totient is φ = 74545749792.

The previous prime is 74551420649. The next prime is 74551420673. The reversal of 74551420661 is 16602415547.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (74551420649) and next prime (74551420673).

It can be written as a sum of positive squares in 2 ways, for example, as 66200202436 + 8351218225 = 257294^2 + 91385^2 .

It is a cyclic number.

It is not a de Polignac number, because 74551420661 - 2²² = 74547226357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74551420631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2815670 + ... + 2842023.

It is an arithmetic number, because the mean of its divisors is an integer number (18639272883).

Almost surely, 2^74551420661 is an apocalyptic number.

It is an amenable number.

74551420661 is a deficient number, since it is larger than the sum of its proper divisors (5670871).

74551420661 is a wasteful number, since it uses less digits than its factorization.

74551420661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5670870.

The product of its (nonzero) digits is 201600, while the sum is 41.

The spelling of 74551420661 in words is "seventy-four billion, five hundred fifty-one million, four hundred twenty thousand, six hundred sixty-one".