742505661 has 6 divisors (see below), whose sum is σ = 1072508190. Its totient is φ = 495003768.

The previous prime is 742505653. The next prime is 742505669. The reversal of 742505661 is 166505247.

It is a happy number.

742505661 is a `hidden beast` number, since 7 + 42 + 50 + 566 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (742505653) and next prime (742505669).

It can be written as a sum of positive squares in only one way, i.e., 568107225 + 174398436 = 23835^2 + 13206^2 .

It is not a de Polignac number, because 742505661 - 2³ = 742505653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (742505669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 41250306 + ... + 41250323.

It is an arithmetic number, because the mean of its divisors is an integer number (178751365).

Almost surely, 2^742505661 is an apocalyptic number.

It is an amenable number.

742505661 is a deficient number, since it is larger than the sum of its proper divisors (330002529).

742505661 is a wasteful number, since it uses less digits than its factorization.

742505661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82500635 (or 82500632 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The square root of 742505661 is about 27248.9570626107. The cubic root of 742505661 is about 905.5239118192.

The spelling of 742505661 in words is "seven hundred forty-two million, five hundred five thousand, six hundred sixty-one".