61621749 has 24 divisors (see below), whose sum is σ = 104516160. Its totient is φ = 35150760.

The previous prime is 61621739. The next prime is 61621751. The reversal of 61621749 is 94712616.

It is not a de Polignac number, because 61621749 - 2⁸ = 61621493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61621739) 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, 107634 + ... + 108204.

It is an arithmetic number, because the mean of its divisors is an integer number (4354840).

Almost surely, 2^61621749 is an apocalyptic number.

It is an amenable number.

61621749 is a deficient number, since it is larger than the sum of its proper divisors (42894411).

61621749 is an frugal number, since it uses more digits than its factorization.

61621749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1158 (or 581 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 61621749 is about 7849.9521654594. The cubic root of 61621749 is about 394.9826387712.

The spelling of 61621749 in words is "sixty-one million, six hundred twenty-one thousand, seven hundred forty-nine".