61357639 has 4 divisors (see below), whose sum is σ = 70123024. Its totient is φ = 52592256.

The previous prime is 61357633. The next prime is 61357651. The reversal of 61357639 is 93675316.

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

It is a cyclic number.

It is not a de Polignac number, because 61357639 - 2¹⁹ = 60833351 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 (61357633) 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, 4382682 + ... + 4382695.

It is an arithmetic number, because the mean of its divisors is an integer number (17530756).

Almost surely, 2^61357639 is an apocalyptic number.

61357639 is a deficient number, since it is larger than the sum of its proper divisors (8765385).

61357639 is an equidigital number, since it uses as much as digits as its factorization.

61357639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8765384.

The product of its digits is 102060, while the sum is 40.

The square root of 61357639 is about 7833.1117060846. Note that the first 3 decimals coincide. The cubic root of 61357639 is about 394.4175338706.

The spelling of 61357639 in words is "sixty-one million, three hundred fifty-seven thousand, six hundred thirty-nine".