101902421 has 4 divisors (see below), whose sum is σ = 101929644. Its totient is φ = 101875200.

The previous prime is 101902417. The next prime is 101902447. The reversal of 101902421 is 124209101.

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

It can be written as a sum of positive squares in 2 ways, for example, as 41280625 + 60621796 = 6425^2 + 7786^2 .

It is a cyclic number.

It is not a de Polignac number, because 101902421 - 2² = 101902417 is a prime.

It is a super-2 number, since 2×101902421² = 20768206811322482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 101902393 and 101902402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101902621) 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, 6890 + ... + 15851.

It is an arithmetic number, because the mean of its divisors is an integer number (25482411).

Almost surely, 2^101902421 is an apocalyptic number.

It is an amenable number.

101902421 is a deficient number, since it is larger than the sum of its proper divisors (27223).

101902421 is an equidigital number, since it uses as much as digits as its factorization.

101902421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27222.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 101902421 is about 10094.6729020806. The cubic root of 101902421 is about 467.0838314535.

The spelling of 101902421 in words is "one hundred one million, nine hundred two thousand, four hundred twenty-one".