49721989 has 2 divisors, whose sum is σ = 49721990. Its totient is φ = 49721988.

The previous prime is 49721981. The next prime is 49721999. The reversal of 49721989 is 98912794.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32433025 + 17288964 = 5695^2 + 4158^2 .

It is a cyclic number.

It is not a de Polignac number, because 49721989 - 2³ = 49721981 is a prime.

It is a super-2 number, since 2×49721989² = 4944552380232242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (49721981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24860994 + 24860995.

It is an arithmetic number, because the mean of its divisors is an integer number (24860995).

Almost surely, 2^49721989 is an apocalyptic number.

It is an amenable number.

49721989 is a deficient number, since it is larger than the sum of its proper divisors (1).

49721989 is an equidigital number, since it uses as much as digits as its factorization.

49721989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 49.

The square root of 49721989 is about 7051.3820631136. The cubic root of 49721989 is about 367.7190795787.

The spelling of 49721989 in words is "forty-nine million, seven hundred twenty-one thousand, nine hundred eighty-nine".