20201531642 has 4 divisors (see below), whose sum is σ = 30302297466. Its totient is φ = 10100765820.

The previous prime is 20201531639. The next prime is 20201531687. The reversal of 20201531642 is 24613510202.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 15853579921 + 4347951721 = 125911^2 + 65939^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5050382909 + ... + 5050382912.

Almost surely, 2^20201531642 is an apocalyptic number.

20201531642 is a deficient number, since it is larger than the sum of its proper divisors (10100765824).

20201531642 is a wasteful number, since it uses less digits than its factorization.

20201531642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10100765823.

The product of its (nonzero) digits is 2880, while the sum is 26.

The spelling of 20201531642 in words is "twenty billion, two hundred one million, five hundred thirty-one thousand, six hundred forty-two".