61657749 has 24 divisors (see below), whose sum is σ = 92282112. Its totient is φ = 39644640.

The previous prime is 61657747. The next prime is 61657751. The reversal of 61657749 is 94775616.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (61657747) and next prime (61657751).

It is not a de Polignac number, because 61657749 - 2¹ = 61657747 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61657747) 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, 29007 + ... + 31059.

It is an arithmetic number, because the mean of its divisors is an integer number (3845088).

Almost surely, 2^61657749 is an apocalyptic number.

It is an amenable number.

61657749 is a deficient number, since it is larger than the sum of its proper divisors (30624363).

61657749 is a wasteful number, since it uses less digits than its factorization.

61657749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2177 (or 2174 counting only the distinct ones).

The product of its digits is 317520, while the sum is 45.

The square root of 61657749 is about 7852.2448382612. The cubic root of 61657749 is about 395.0595413102.

The spelling of 61657749 in words is "sixty-one million, six hundred fifty-seven thousand, seven hundred forty-nine".