13992021 has 10 divisors (see below), whose sum is σ = 20901782. Its totient is φ = 9327960.

The previous prime is 13992019. The next prime is 13992023. The reversal of 13992021 is 12029931.

It is an interprime number because it is at equal distance from previous prime (13992019) and next prime (13992023).

It can be written as a sum of positive squares in only one way, i.e., 9090225 + 4901796 = 3015^2 + 2214^2 .

It is not a de Polignac number, because 13992021 - 2¹ = 13992019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13992023) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 86290 + ... + 86451.

Almost surely, 2^13992021 is an apocalyptic number.

It is an amenable number.

13992021 is a deficient number, since it is larger than the sum of its proper divisors (6909761).

13992021 is an equidigital number, since it uses as much as digits as its factorization.

13992021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172753 (or 172744 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 13992021 is about 3740.5909960860. The cubic root of 13992021 is about 240.9684307517.

The spelling of 13992021 in words is "thirteen million, nine hundred ninety-two thousand, twenty-one".