1021650442 has 4 divisors (see below), whose sum is σ = 1532475666. Its totient is φ = 510825220.

The previous prime is 1021650439. The next prime is 1021650449. The reversal of 1021650442 is 2440561201.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2440561201 = 13 ⋅187735477.

It can be written as a sum of positive squares in only one way, i.e., 757295361 + 264355081 = 27519^2 + 16259^2 .

It is not an unprimeable number, because it can be changed into a prime (1021650449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255412609 + ... + 255412612.

Almost surely, 2^1021650442 is an apocalyptic number.

1021650442 is a deficient number, since it is larger than the sum of its proper divisors (510825224).

1021650442 is an equidigital number, since it uses as much as digits as its factorization.

1021650442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510825223.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 1021650442 is about 31963.2670733140. The cubic root of 1021650442 is about 1007.1653491433.

The spelling of 1021650442 in words is "one billion, twenty-one million, six hundred fifty thousand, four hundred forty-two".