19772001 has 6 divisors (see below), whose sum is σ = 28559570. Its totient is φ = 13181328.

The previous prime is 19771987. The next prime is 19772029. The reversal of 19772001 is 10027791.

It can be written as a sum of positive squares in only one way, i.e., 15610401 + 4161600 = 3951^2 + 2040^2 .

It is not a de Polignac number, because 19772001 - 2⁶ = 19771937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19772201) 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, 1098436 + ... + 1098453.

Almost surely, 2^19772001 is an apocalyptic number.

It is an amenable number.

19772001 is a deficient number, since it is larger than the sum of its proper divisors (8787569).

19772001 is a wasteful number, since it uses less digits than its factorization.

19772001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2196895 (or 2196892 counting only the distinct ones).

The product of its (nonzero) digits is 882, while the sum is 27.

The square root of 19772001 is about 4446.5718255753. The cubic root of 19772001 is about 270.4063428904.

Adding to 19772001 its reverse (10027791), we get a palindrome (29799792).

The spelling of 19772001 in words is "nineteen million, seven hundred seventy-two thousand, one".